Seriously, where are they?

Dont you think it would add alot more complexity and fun to game if we had smokes?

Pretty silly, Nanovision, Tracker, Visor Enhance all render these useless. Chaff Grenades for jamming radar would be a lot more interesting imo.

I'm imagining brutal fight under smoke cloud on the Wall Street map, and I like it!

Nanovision doesnt have a large range, it'll also help fixing line of sight issues in game(in most maps player will have a huge percentage of the map visible to him, it causes you to get killed from some guy who wasnt even looking for you) Also it'll add some tactical depth.(you'll likely understand what i mean if you ever played a game with smoke greneades with it) You should remember, nano vision actually is worse for seeing things when they are out of the range of heat cam.

Smoke grenades would add nothing to the game and would only be used by people messing around. The only use I can see for them would be in Assault for the attacking team.

Smoke grenades would be pointless on maps like Lighthouse, Santuary, etc where snipers almost always run Visor Enhance. Everyone going into smoke would use Nanovision. All it would do is hide people from enemies at long range who do not have Visor Enhance but hey, isnt that what Cloak is for?

Also your argument is pretty weak. Just because smoke grenades add gameplay depth to a different game (with different gameplay and mechanics) doesnt mean it will add to Crysis 2. Im sure those games dont have Cloak, Nanovision and Visor Enhance.

Does visor enhance tag even when in stealth? and do you know how long it's gonna stick on the guy? And also for your argument ive only seen somebody use visor enhance like 3-4 times in my team(im lvl 42 with 50+hours ingame so that should give you and idea how rare it is) For me blind spot in sniper is a must. People will hunt snipers and max radar is always the best tool for that.

Ive shortened it up with tactical depth discussion because im kinda too lazy to explain everything atm. I will expect it to work as the other games unless we can prove this game has a mechanic that will prevent it. And im discussing that atm. It's not a weak argument, just think about what you read a bit more carefully before replying next time.