Flashing my wad (bankroll people, bankroll) has only had yielded two noticeable results in my personal experience.
I doubled a 42(6) against a 5 the other night (knew the dealer had a facecard under). It got a shocked response from the only other player but not many people noticed. When I split 10's against a 5 (knew it was 15) everyone was squealing "no, no, no" Had to try and draw less attention after that. I don't really listen to the angry remarks of people who think you're "ruining the flow of cards".. then again I've learned to cope politely with inferior minds giving me advice on everything in life. For your index question I can't find the numbers but the big 3 (Insurance, 16v10, and 15v10) account for about 60% (of which insurance is 30%) of all possible gain from strategy deviations and the I18 about 90%. If you play shoe games and want to throw out most of your strategy variations except insurance I think you give up a bit more than 0.1% of advantage. If you play single deck with good rules you would be giving up more and I would advise against it. If you're straight counting a shoe game I would guess the best way to make money is a simple count, the most basic strategy changes, an aggressive bet spread and A LOT of time counting/wonging.
Those are both moves a typical ploppy would make, must have been the cash that scared them... If you're standing 16v10 would you not also be standing on A7vA??
but I believe you can find those numbers in “Blackjack Attack” and “Theory of Blackjack.”
I mistyped, I meant I had hit a 16v10, in other words, I was just playing strict basic strategy, had lost about $100 or $200 bucks (big money at Slotsafun), and dug into the "wad" for more.