I run DSC fully off in the dry. I find the car does not behave the same way at the limit with DSC or MDM on. I feel the car is smoother and more controlable to subtle inputs with DSC off. Further, since I am running a square set-up, this means that the wheel diameter ratio front to rear is slightly different than stock. So DSC believes that the rear tires are spinning slightly faster than they should and kicks-in more often.
I will however use MDM running the first time on a new track, or in the first laps of the day when the track is still dirty (unknown track conditions). Hey the help is there, might as well use it
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I used to run DSC off in the wet also, until I was served I nice piece of humble pie. I hit a small puddle of water going straight at 110mph, the car snapped sideways so fast, I never saw it coming
. I am lucky that I did not total the car or get hurt, but it did cost me quite a few $$ to fix
. I am not a newbie (been tracking cars for almost 20 years), but no Senna either, so I now keep the nannies on in the wet.
As for novice students, I agree it "depends" (not the diapers). When they are humble and want to learn, I am OK with them swithing off the aids. It is their car so I leave it up to them. However, some of them come with extremely powerful machines and just want to show off how good they are, then I insist "all aids on", it's my life on the line after all
.