OK, I get it. If you get it RIGHT in one point i will get WORSE in another point...
On the other hand, that's one of the things that makes live sound so interesting! There is ALWAYS more than one way to skin the cat!
There is "right" (which rarely happens in a room with more than a couple of people listening), and then there is "acceptable".
I would argue that 99.99999999% of all sound systems fall in the Acceptable or unacceptable categories.
Almost none are "right" or perfect for every seat. So it is all a matter of compromise.
The "trick" is understanding how important the compromise is and what the consequence of the compromise is.