Disclaimer:
Okay let me first start of by saying that I do enjoy the Warden Class, and I do know they can be an effective defender if built right. The point of this thread is to show that Warden's can easily slip from being a defender to a tank, and that as a Defender they have some major hurdles they have to overcome. Also many of these ideas are not new, or orginal. I made this thread to express my frustration with the Warden Class verse other Defender Classes.

The Reasoning:

The Baseline:

The first thing I need to explain here is what is a Defender and what is a Tank. While these are common enough term here I want to be clear what I mean. To that end I will define both what a Tank is and what elements turn a character from a Tank to a defender.

Tank: Is simply a PC that is extra tough. This can be achieved through a number of different tactics from having Insanely High Defenses, to being able to heal pretty much any damage you take, or just having so much HP that you don't care if you get hit. Most Tanks have elements of all three basic tactics.

Next up is what makes a Defender. To me there are a few key traits that turn a Tank into a defender.

Marking: This is simply the ability to lay down marks. This is the building block which all defenders rest on. You have to be able to mark you enemies to be able to deter you enemies from attacking you squisher. However by itself having a Mark does not make you a defender.

Mark Punishment: This is what turns a defenders mark into something to be feared. This can take many forms but the idea here is that a Defender can react to someone triggering his mark in a way that will make the enemy think twice about attacking an ally.

These are the base two factors but most defenders need at least one of the following factors as well.

Stickiness: This is your ability to keep you enemies from moving away from you. If you are able to keep enemies close to you and away from you allies then they really only have the option of attacking you. This means that you are doing your job.

Lure: This works similar to Stickiness and is many ways similar. This is your abilty to draw enemies to you. If you can keep drawing the enemies to you and away from allies you are creating a situation similar to what Stickiness does where the enemy doesn't have a choice but to attack you.

Mobility: This is you ability to chase after enemies and follow them. If you stay on the enemy 24/7 you create a situation where you are always up in the enemies business and there by increase the enemies incentive to attack you over allies. Once again this works in a fashion similar to Lure and Stickiness.

Ranged Punishment: If you can't do one of the above three then you need to have a way to make you Mark Punishment effective at range that way even if you are not up in the enemies business you are making it harder for them to attack you allies. This is primarily used by you Swordmages and Paladin as a way to make up for their somewhat lack of the above factors.

Now the best Defenders have bits of most of these factors working together and balanced against each other. Focus to much on anyone aspect and you end up with a less effective whole. For example Mark Punishment needs to be Balanced by your Tank ability if you are to tanky in comparison to your Mark Punishment you are not being a effective defender, like wise if you focus to much on Mark Punishment you will end up dead as you can't withstand tha attacks coming your way.  

The Warden:

Okay now that we have talked about what a Defender is lets look at the Warden and how it fits in.

Tank: Here the Warden really shines they are by far one of the toughest class in the game and really have it all when it comes to being a Tank.

Marking: Once again a Warden is very good at this easily able to lay down multiple marks each round so long as he can get close or keep enemies close.

Mark Punishment: This is the Warden's single biggest weakness as a Defender. The base mechanics are fine attack an enemy when they voilate you mark. This is what the Figther does and it works well for him, but then why does the Warden have issues. The issue here is support between PHB 2 and PP there is not a single feat that really impacts your ability to punish a mark. While if we look at the Fighter between PHB and MP there are 9+ feats that all they do is boost the potency of their Mark Punishment. This doesn't even include the PP side of things which makes it even worse for the Warden. This means that while the Fighter can make his Mark deadly the Warden really cannot which puts the Warden at a sever disadvantage.

Stickiness: At a base line the Warden lacks the ability to do this. Now when you add in some of there powers a Warden can easily pull this off, but that creates a different problem for the Warden. They are forced into picking certain powers if they want to be sticky. This limits the varaity of powers you select if you want to be a effective defender.  

Lure: Once again at a base line the Warden lacks this ability and needs to rely on his powers to come to the rescue. This has the same issue as Stickiness that it limits the possible combination of powers just so you can make an effective defender. Stormheart Wardens get some feat support in this area and some support in their Class feature but it is minimal.

Mobility: Yet again at a base line the Warden lacks this ability and needs to rely on his powers to come to the rescue. This has the same issue as Stickiness that it limits the possible combination of powers just so you can make an effective defender. Wildblood Wardens and Stormheart Wardens have some feat support in this regard but it is once again minimal.  

Ranged Punishment: The Warden does come with a version of this but it is lacking to say the least. The Warden's Grasp doesn't do much to discourage or hinder you enemies for attack your allies and it suffers the same issue as the Warden's Mark punishment, lack of support.

The Result:

Okay now having expressed the baseline and seen where the Warden fits in on the base line lets talk about how the factors in the baseline interact with regards to the Warden. Overall the Warden has most of the basic tools to be a defender but there are two key areas he has issues with.

Tank vs Punishment: Wardens are extremely Tanky, but do not have strong mark punishment. This creates a situation where even with their mark and punishment the choice of many enemies will be to attack the Warden's allies over the Warden. The reason being is that the when the enemy does a cost benefit analysis it will usually come up that the minor threat of an attack from the Warden is outweighed by the ability to kill of the Warden's Squisher allies. Basically the Warden's ability to punish with their Mark is not balanced against the fact that they are extremely tough.

Powers: This may a bit controversial but I believe is warranted. The Warden depend on his power to fulfill the role of a defender. The issue here is that by having to rely on his powers if he selects the wrong powers he will not be effective in his role. This creates a bad choice for players as they are forced to take certain powers just to do their job. Other defenders rely on their powers to enhance their ability to defend so if they pick a bad power it does not stop them from being a defender just diminishes their ability slightly. This once again put the Warden in a bad posistion verse other Defenders.

With these two glaring issues it is easy for a Warden to fail at being a Defender and it makes realy hurts the class. This becomes even more evident when you begin comparing the Warden against other Defenders. Now while a Warden can be an effective defender these issues will always hold them back.

Disclaimer 2: I want to reiterate I am not trying to bashe the Warden or trying to say they can't be effective defenders but that when you compare them to other defenders they are found lacking. That from a Character Optimization stand point this is a bad thing and should be addressed and taken into consideration when building a Warden.

Out of the box a Shielding Swordmage has some of the best defending ability, and like the Paladin and Fighter also has support to enhance his mark.

The biggest issue is that the Warden has NO ability to enhance his primary marke punishment Warden's Fury while every other defender has multiple ways to do this. No one mark is properly effective at the higher level of play with out some investment.

Now I am not saying that other Defenders don't have their other issues but I am saying that the lack of support and the structure of the Warden's defending ablity makes it much easier for a Warden to become a Tank not a Defender as I defined it.

Most of the Warden's Powers don't enhance his mark punishment at all. They just allow him to be more sticky, have greater lure, or more mobile, and not all of the warden's powers do these things.

There a fairly large subset of powers that do these things but if you do not invest in them you are not being a defender which creates a situation where the Warden if he picks the wrong powers simply cannot fufill his role as a Defender. Where other defender classes have most of the basic mechanics to be a defender built into their class features, and Feats and Power selection just enhances their abilities.