Sorry for the intrusion. I am a PT and sub scap is generally never an issue.

Are you guys meaning supraspinatus? That’s the first RC muscle that becomes involved.

BTW, RC issues have a weird pain referral/radiation to the biceps region & rarely is the biceps involved as well. You’ll know you have a potential biceps issue (generally long head) when you curl and your arms aren’t supported (like on preachers). DB work in particular is a bitch.