Thats a blanket statement. Of course, I go ATG to get my BBS shave. Some areas get the near ATG pass since ATG isn't feasible due to its location and the size of the straight razor.
Too many passes, too much pressure, and not enough lather are my reasons for an irritated area. I rarely get in grown hairs and when it happens, its very minor and gets worked out easily and unnoticed by others.
Some shavers have problems with ATG, but I am not one of them.
You just have to find out what works for you.
Pabster