In general, you're wrong. You only have to look at the exceptionally competitive world of racing competitions in GT4, such as the inter-forum Board Challenge or the Weekly Race Series, to find that top drivers essentially never use aids. Believe me when I say that competitors in those series are doing whatever they can to go faster, and are not keeping aids off out of principle. In certain rare circumstances, such as when a car has bad wheelspin, a TCS setting of 1 (but never more) does give an advantage. Also, extremely rarely, an ASM Understeer setting of 1 allows certain cars to be driven with more precision and speed. However, in Arcade Mode, having no driving aids is always fastest, because the levels of TCS are non-adjustable and are set too high to be useful. In general, avoiding wheelspin is largely achieved by selecting a much higher gear than is "recommended," rather than by activating the traction control. It's true, though, that for more casual players, having aids on can be faster in powerful and/or ill-handling cars. I apologize for the off-topic post, but I couldn't help but refute that statement.