the hair length is the "tradition" that Paul is dealing with...as seen at 1 Corinthians 11:4 where it says - "Every man who prays or prophesies with his head covered dishonors his head."
Lets remember, This is not a teaching of Christ!
Paul does not quote Jesus here, this is not a central part of the Christian faith.
Rather this is a "tradition" that Paul knows will be very helpful to people and will bring a good reputation to people and to the church as a whole
But to be honest with the people he was writing to, Paul shows that he understands that not everyone will agree with this "tradition"
and as a way to toss a bit more weight behind his words, Paul here at 1 Corinthians 11:16 lists the only real "authority" he had to list.
"If anyone wants to be contentious about this, we have no other practice--nor do the churches of God."
See how Paul does not appeal to the words of Christ to support his view on the correct hair length?
See how this is not , clearly not a matter that is tied to salvation or the message the Christ gave to us,
All Paul has to support this tradition is for him to point to the other churches that follow this same tradition.
Paul could not point to Christ's words to support the tradition.
This is clearly a simple "tradition that Paul taught these people.
And we have looked at this in the comments I have posted where I show how the "covering" was the hair, and how a man that has his head "covered" is actually just talking about a man who has his hair too long according to tradition.
and this is why when Paul says that if a women does not cover her head she should have her head shaved!
Why?.....cuz its the same idea being that her hair is too short!!!!!!!