From what i can gather, offline tunes for A-Spec races are usually tuned to follow the driving line spot on and balanced steering so theres no under/oversteer, the AI isnt the smartest so an offline tune is to just get you in front.
Online, your up againts real folk who will bump you, cut you up and everyone is fighting for the driving line. u need a car with good accel for all the bumps and knocks so you dont get slowed too much and u can get back upto speed and back in race more effectivly and u need a car that can get round a corner on a lot wider angle than the perfect line. sometime your gonna have to go outside, others inside and if you use a tune thats too balanced your not gonna make the corners and will lose race more easily. thats my theory anyway.
I'm not going to make a tune for my car be a tank, because people online pass you inside, outside, over you sometime... No way for me. This is not passing, this is forcing the way anyway anyhow. When i meet "racers" like this online ,and there is a lot of them, i simply try another room..... Generaly i race with people i know they're clean.
Like this don't need a tank. This is what i 'm looking for in this game, i'm not saying that they are wrong, everybody have fun the way he want. But not for me and my tunes that are made to be driven nicely. Not like an "elephant in the middle of a crystal shop...."
If i want to bump, and i like it sometime, i play burnout. It's a fantastic game for this.