When I was a student (at all 3 music schools I attended) we were all expected to perform our SOLO repertoire from memory on recitals and semester juried exams. For ENSEMBLE music (including duets) reading from the score was allowed. It wasnt just the guitar studio...same with the piano department.
This translated to memorizing about 15 minutes worth of music per semester. It wasnt too bad, but caused me a lot of stress, as often I'd be worrying so much about memory that I neglected other parts of the performance. (I was quite a nervous performer back then, anyway)
Its probably a good thing for students to do this. I'm not bothered when I see performers use the score, though.
Now, I'm allowing my students to use music for Jury exams, but I still want them to memorize for recitals. I'm not teaching at a prominent music school, though. Honestly, I'm not sure what I prefer.
The last full-length recital i performed was from memory; I don't perform very often now though, and most of it is accompanying, so I don't have the pressures of memorizing lots of music in a short time.
2015 John H. Dick
1994 Larry Breslin ("Deerhead")
1952 Vincente Tatay