Insurance Play - Question for Don

I just read something that I never heard anywhere before. When making an insurance decision (using Hi-Lo), should one disregard the dealer ace for purposes of the TC? For example, suppose the RC is 9 factoring in all cards on the table including the dealer ace. Would it make sense to increase the RC by 1 and use a RC of 10 for the insurance decision (effectively ignoring the dealer ace)? After all, insurance is a bet that the dealer has a 10 in the hole. Why reduce your count by 1 when the ace has no bearing in this particular decision?

Of course, once the dealer closes insurance then the RC goes back to 9. While it won't make or break one's game, but it would make the insurance decision slightly more accurate, no?

Thanks,
MJ