From what I've seen, dead man recon tends to boil the game down to raw skill (of the living player(s)). If it's teamwork, it's passive teamwork. Eliminated players aren't actively involved in distracting the enemy, or flanking them, or any of the things I would personally consider to be teamwork. Instead they're simply providing the living player(s) with information which nullifies any potential strategy the enemy is using and results in merely skill-based confrontation.
If you have good aim and work as a team, you'll most likely win.. there's not much strategizing to do, even in big maps like c1.
Because it isn't necessary. Who needs strategy when your dead teammates can simply tell you where everyone is?
For example, I'm rushing high on castle1 (4 vs 4) and I see that DirtyTaco and Bob have just been killed almost simultaneously by the same opponent. Well, I knew DT was going backdoor -> middle, so I assume that they both lost a firefight in the middle of the map. Now, I also quickly consider the fact that there's probably two opponents in the middle instead of one, since both of them getting killed by a single guy at once seems improbable (there were probably other distractions). So, very quickly, I consider my options in what is now a 2 vs 4 round. Instantaneously I would switch into a defensive position, either chooising to backtrack towards my backdoor/door area...
It would be neat if the game were played more like this, but in reality, it doesn't matter where your teammates are when they die, because they can simply tell you where the enemy is after the fact.
I can't remember the last time I recon'd "hes behind the crate" or "hes under so and so" because DP moves way too fast for the guy to still be there by the time you've received the recon and gone all the way there.
Perhaps you personally don't, but the er33t demos I've seen are filled with things like "tower", "V", "X", etc., designating exactly which bunker the enemy is at. You know where he is. He knows where you are. The end result is a head on match of raw skill. There's little room left open for outsmarting, ambushing, sneaking around, or pretty much any other strategy. It's almost solely confrontation skills.
I'd like to thank DT for spelling out his reasoning in a logical fashon, but I do not think that playing with dead-man recon brings about the same level of teamwork and strategy that playing without it does. Hear me out. At one point, dead-man recon may have taken some skill, but these days with things like voice recon, it's trivial to tell your teammates where the enemies are.
Say you have a 5v5 match and you have an excellent game plan worked out. Your team moves into position and eliminates the first opponent.
... and now the enemy knows your strategic positioning because the eliminated player is reporting it. Strategy is almost pointless once the first guy is out. It's straightforward confrontation from there on out. You can't set up traps, ambushes, or surprise attacks (things that require active teamwork) very well because the enemy players know where you'll be. You can't sneak into the base because the dead player(s) will report your position, even if you used some active teamwork to reach a path not normally accessable, and you will have to face a head-on confrontation with the defense. Again, raw skill is involved there. The strategy is pointless.
In fact, there is not much strategy offered at all, as digi mentioned. It's mostly about how fast you can move and how well you can aim. That's how it is with dead-man recon.
Without it, though, I think a whole new realm of latent gameplay could be opened up. Maybe I'm wrong, but I think it would be neat to give it a chance. Instead of being geared toward individual confrontational skills, it could potentially move more toward active teamwork and strategy. Real game plans, not plans that only last half a second because the enemy knows where you are.
Now say you're the team that has an eliminated player. With dead-man recon, you can all be lone gunman going after individual goals and have the eliminated player(s) tell you where the enemy is. It's not critical to work together much, because the enemy can't simply sneak around you, and if they do manage to grab the flag, you'll know exactly what path the flag carrier is taking without even having to think. You're just being told. While this is not void of teamwork or strategy, it comes close in my opinion.
Without dead-man recon? Now you're outnumbered and outgunned. It's at this point that cooperating with your remaining teammates becomes
critical. You can't just merrily run off in your own way and attack the enemy, because you won't necessarily know where the enemy is. You need a game plan, and you need one that's better than your enemy's. It's no longer just a matter of running and shooting. You have to outsmart the enemy. Do something unexpected, but you also need your teammates to cover your arse. Outplay. Don't simply outrun or outaim.
That's teamwork at its finest.