@ thefastone
This is how I understand it. This is what my experience is. (Others may have other takes on it.)
The indicator at red is indicating temperature, not wear.
The brightness of the indicator is indicating temperature, not wear.
When tires actually get worn, they start showing as black in the indicator.
Tire temperature (what amounts to feeling like wear - so I usually call it wear even if it's not actual wear just warmth) exists all over.
In shorter races, tire temperature doesn't really get to a point where you'd notice. So in shorter races, if your aim is for speed & winning, there's no point in using anything but soft... Unless you're going for more challenge for the sake of it. Because it's not like you're going to warm up sports hard tires in 2 laps anyway.
You can only get actual tire wear (not just warmness) in practice mode with tire wear ON, or in online mode with tire wear ON, (or in just some aspec & bspec races - like endurance section).
And there's something hinky about tire warmth & tire wear that doesn't match up with realism as far as hard tires vs soft tires, in gt5.
Whether you have tire wear on or off... it's the warmth at issue, and either way, hard tires are never a better choice (for speed/grip) than softs in gt5. This shouldn't be the case but it is.
The person who posted about comfort soft being grippier than sports hard... There's something to that because in a way, in some cases, it would make sense in a long race to favour sports soft over racing hard. That shouldn't make sense, I know.
Softs just seem to have a longer plateau of "nice warm". They start out nicer, and they stay at the nice place longer. And with tire wear on, they don't wear out faster than hards... which none of this is realistic at all, but that's the way it is in gt5.
Really what it amounts to, as I see it, is that if tire wear is off... You can kind of, let's say in the middle of a race, just STOP somewhere (not in the pit), and wait, and the tires will, I guess, cool off. And then it's like you haven't used them. So in theory, in a long race with tire wear off, you can maybe take it easy with the tires for awhile, and get them to "come back".
I haven't tried that or run any repeating experiments with it. Would seem rather silly anyway.
But that's the point... I guess they (the game makers), saw it as irrelevant to have tires actually wear out in shorter races. Because it just wouldn't matter because the tires aren't even heating up in 2 laps, let alone wearing out. And in longer races, they do put tire wear on, because then you could sort of use a cheating strategy of taking it easy on the tires over the course of the race or something. I don't know.
This is my take. When we first got the game, the tire wear / tire warmth issue, was the first thing we noticed as not making any sense.
Others have various theories & opinions on the matter.
One thing is sure, no matter what the opinion, everyone agrees there's something just not right that makes everyone unhappy about tires in gt5.