some interesting posts here!! Horns in open wheelers = yes please, i nearly cried in the BF1 when i pressed horn and a whole lot of nothing happened! or hand gestures would be fun but as it ws mentioned before, deciding which gesture, which direction, steering etc would be a lot of bother.
OO about the whole blinkers doing what thing. If i were hurtling down a straight at the speed of sound and i see some guy in my mirrors coming from behind quite quickly, id try and move over to one side if i could without ruining my lap or just expect him to pass. The blinker thing is a good idea but i use my blinkers if, say, i want to pull into the pit lane and someones near me, let them know im pulling off the track. Imagine if youre driving towards the pit lane on BlackwoodGP Standard. Theres someone behind you, catching up. You indicate left to say youre pitting and he thinks' hmm he wants me to overtake on the left, here goes'. You turn into the pits and you leave a nice dent in the side of his car!
What a long post. I shut up now.