If your imaging is crystal clear and you can easily "sense" exactly where each instrument is located between (and occasionally beyond) the speakers then you probably can live without treating the reflection points.

If you read about crystal clear imaging and wonder what they're talking about, you probably need to treat the reflection points

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