Hi, Fred:
I have seen Corky and Shirley in person. They are not tall, perhaps 5-7 and 5-5.
Luca Bericci and Loraine Barry, world Standard 5 dances top couple, are very tall. Many times I have heard that the commentators would say that they were very impressive due to their height. I agree and I do like this couple a lot.
On the other hand, I have seen taller, lower- level competitors, in both Standrad and Latin, seem to stand out. This is to say, their dances are much noticeable that if they are not dancing correctly, it is easily pick up by spectators or judges.
Keh