Yes, that's all well and good, but here's the thing: crits force you to take into account that there is a risk in everything you attempt. TF2 isn't chess. You can't sit there and depend on your analysis of the situation every time. Sometimes you just have to say "screw it" and take the risk. Sometimes you die. I'm against no-crit days.
My only complaint is our ridiculously long respawn times. We should really change it to 10-15 seconds max. I know the argument against it: "If you don't like long respawn times, don't die. :P" Sorry, but that's a stupid argument, because I don't think I've ever played a round of TF2 where nobody died. You hear it all the time from people on voice-chat, complaining about the long respawn. It's really annoying having to wait 20+ seconds to get back into the action.