I wouldn't accept it. What he means by every other stone is if you look at your picture every other stone is a perfect rectangle (90 degree cuts). They only cut angles to make the coping round on every other piece. What they should do is have angle cuts on every piece of stone not every other one.
Ohhhhh. Now I get it. Thank you so much for explaining. Except for the askew joints and seams, I couldn't figure out why else it did not look right. Now, when the foreman or PB comes out to look at it, I have a better understanding to explain why I'm disappointed. It's just me - I hate these things. I wish I knew more about how things should be done on pool building, but I don't. That's why I hired a PB to look out for me. It's unsettling to depend on someone you don't know to do the right thing. They may, they may not. Thank you, thank you. Suz.