After several discussions on here, I did a few experiments with my hold button & can confirm that if it's all working ok, if you put it on while you're doing 70+ miles an hour in D - it shouldn't kick in, mine repeatedly worked as the speed dropped to 68mph, at which point the revs went up to around 3500 revs, nothing too scary, your gearbox shouldn't end up in pieces all over the road (
usal disclaimers apply)- maybe a bit of a shock for any tailgaters though
I tried it in S2 as well, memory getting sketchy here but I think it was around 45mph upper limit, again it won't kick in if the speed is excessive.
You can't polish a turd - but you can roll it in glitter.