I understand that, but Thomas hasn't shown this "plate discipline" that you speak of. He doesn't walk a lot for a guy with such great "discipline", he doesn't get on base at a great clip, and he strikes out a ton.
Now, since it appears that you lack reading comprehension skills, here is WHY I said that his .358 OBP doesn't translate well into the majors: he is putting up those numbers in AA, not at the major-league level. Minor league statistics CAN be translated into a set of MLB stats, and the two correlate surprisingly well. For instance, a hitter in AAA with a .300+ EqA in an average run environment could be reasonably expected to post a .260-.270 EqA (about MLB-average) in the majors.
Now, that is how the stats translate from a guy dominating AAA, not a guy putting up otherwise average numbers in AA. Therefore, a .358 OBP put up in AA won't necessarily translate into a .358 OBP in the majors, not even close.