thing is shaggy, if you are doing aeros, last place you are looking is inside at the cockpit at gauges!!
I do think a properly trained pilot can do with out an aoa indicator and anyone doing aerobatics knows you can stall at any speed - 9g in a extra equates to about 170kts (give or take)
the extra buffets before stalling - just the more G you apply the shorter the period between buffet and departure. To practice finesse I sometimes split s and hold the plane on the buffet at a shade under 5g
but having said that anything that reliably aids safety cant be a bad thing