Bingo. Inverting the speaker only makes sense if you have the center placed on top of your TV. In my case it also helped to put the tweeter closer to ear level but that depends on how high your TV is mounted.

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8