On the surface, this blood pressure bit is a fun thing for the fear it strikes in them for a few seconds. It scares them worse than height weight, but it takes too long to do. Even Thor, who was happy to do it, got annoyed at the time it took. Also, this one isn't going to fly too well with the promoters. Height and weight is funny, and you look like a douche if you complain about it. Blood pressure is asking a little too much.
Shaw always looks annoyed at all fan interactions, lol.