I was asked to tie tehelet for someone according to the Rambam (Temani). Your instructions show 3 winds per chulya. However, you state that there is a machloket as to what Rebbe meant by 7 minimum (maximum 13), i.e., chulyot or windings per chulya. You stated that one view of Rebbe is to have 7 (minimum) windings per chulya. To be yotzai Rav Schachter’s view, and taking into account the shamash length, would it be more ‘proper’ if tying according to Rambam (Temani) to have 7 windings in the first chulya & the rest (the other 12 chulyot) with 3 windings each?

The machloket is really: Raavad (7 wraps) v. Everyone else (3 wraps). I believe that if one want to be “yotzei” the view of the Raavad, he should wear another begged tied according to the Raavad. But if this is too cumbersome and one wanted to integrate the sheeta of the Rambam along with the sheeta of the Raavad (as R. Schachter proposes), my opinion is that one should do 3 “chulyot” of 7 wraps, and the other 4 chulyot of 3 wraps. Furthermore, one should do the three chulyot of 7 wraps in the positions where the Raavad considered them to be “real” chulyot, and one should place the other 4 in the middle position where the Raavad said one could wrap as he wishes. So it would look like this (where x is a double knot):
x
7
x
3
x
3
x
3
x
3
x
7
x
7
x

– Mois Navon