Yes, they are treated the same as sdlxliff locked segments.
Great. Then I'll ask my client to lock them bastards. No pay, is no correction ;). Yep, I can live with suboptimal. I ain't no fool, am I.
(No, you don't need to answer this.)
I've started translation of the memoQ project with locked segments and see that they are so well locked that they aren't displayed. This is different from how locked segments in Studio files are handled. See:
Are segments that have been locked in MQXLIFF files treated the same way as those in SDLXLIFF files? Especially: are they locked/uneditable in CafeTran too?