I had a tutor at uni like that! I had one module, Recontextualising the Vernacular, and I didn't understand it at all. I asked the tutor for help and she said "if you don't get it now, you never will". God I wish I'd complained! I got a third in that module and it robbed me of my overall 2:1 😞

Re correspondence courses though, I think my OU degree is great, although of course we have live tutorials and stuff, it's not all written in.