The MARRS ITC split starts were an outgrowth of our previous marriage to class of spec cars. I'm not naming names, but it's got a rotary engine.

They were fast in a straight line. They were slow in the corners. Some of the mid-pack drivers used poor judgement and when spoken to regarding pounding ITC cars were dismissive using the "spec classes need to bump" point of view. If they jumped the start or got a jump on you at the start, you never were going to get past them unless they went off or hit someone (and then you only got past them if they didn't collect you on their way to a DNF). The stewards were uninterested in "counseling" the offenders. In short, it was making lemonade 'cause all we got was lemons.

Re: ITC pole sitter jumping the start - possible, but I haven't seen the ITC pole sitter do this. I've relied on the second row to speak up if this happened and I haven't heard a peep. If it happens, that'll be the end of the arrangement. My understanding is that the ITC "go" point is when the pole sitter hits the end of the pit wall. The hand out the window is just a signal. For the most part, the 10-12 cars in ITC tend to have good formations and you pretty much can tell when it is time to go.