The main reason is that the starting clamp seems to be a little hard on the string. I wanted to see if the starting pin way would cause less damage to the string.
I never like to pull against a a single clamp no matter what clamp it is. When pulling tension on a main string there is some back tension on the other side of the clamp so that is different.
When you initially pull tension to start a string like your mains I run in two crosses, clamp one and pull some tension on both strings by pulling the string not clamped. I will have full tension n the pulled string and something less that full tension on the string with the starting clamp because of frame friction. Then I pull tension on the next main leaving the string with the starting clamp alone. Now I have two strings with full tension and the one with the starting clamp with something less. When I pull tension to remove the starting clamp I get full reference tension on that main. Then I string two more and starting alternating two mains a side until all mains are done. That way I never get more than 1 main ahead.
When I do crosses I run in the 2nd and 3rd cross and put the starting clamp on the second. Tension the 3rd to bottom cross n order then come backup and do the 2nd and 1st.
EDIT: I also do not like to clamp the center mains at the top of the frame. So if I have a racket where the mains starting the throat I run in 1RM and 2RM. Starting clamp on 2RM and tension 1RM. Ten do two on the left before switching back to the right.
