Whatever Rav Shaul means by kata kephales ("down the head"
in 1C chapter 11), we know that he cannot be
referring to the Kohen Gadol, who wore something
on his head (tzenifot, turbans), as Rav Shaul, very well knew.
If this is what he is asserting, then Rav Shaul would be contradicting the Torah, 
which he never does, of course.  So Rav Shaul would not be standing at 
the door, telling the Kohen Gadol that he could not enter 
the Kehillah until he met the specifications of the dress code.  
We do not know exactly what the men were doing in 1C chp 11, but the 
point is that the "head" of the man is Moshiach and the "head" 
of the wife is her "man" or husband, and there must not be 
anything that dishonors the "head," especially in the 
Kehillah, which is a spiritual and even cosmic environment, 
really, that touches the heavenlies. In short, no one can 
find a prooftext in 1C chp 11 to keep Orthodox Jews out of Messianic 
Synagogues by asserting that their yarmulkes are unscriptural,
which assertion is itself unscriptural.