the single question mark is probably the most effective form of trash talk, even better than the simple 'lol'
it doesn't just point out the bad play the person just made, but every decision they made leading up to the misplay
it's like you're saying 'why in the world would you even consider doing the dumbass shit you just did, much less actually do it'
i highly recommend binding the single question mark to an easily accessible key so you can drop it whenever possible. That scout missed the easy 2shot? single question mark. Med dropped an uber? single question mark. You get a completely bullshit backcap? single question mark.
good luck with your team search, rave.