"Neil
This would force people to use the sector/lap times more to work out how hard to push or sit back and thus make more the races more involved/interesting for everyone.
+1 Once your in the lead and you know the person behind has "hotter/redder" tyres than you, you can back off knowing that even if he starts to catch you you have better condition tyres so you can push to get a bigger lead, showing the condition of the components doesnt really give you any advantage
Showing what tyres people are on, i suppose you would know in real life, but if you pay attention it tells you at the top of the screen at pit stops etc anyway, also the amount of time in the pits would give you a rough idea how much fuel was put in,
but would knowing the fuel/tyre type of every1 in the race make for a better race or ruin it completely?