Looking back, I think the problem was the lack of documentation on what to expect. There are always questions of how many cards should you do in one session, and how you should rate them.
A few days ago I started again, this time using org-drill. As with everything org-mode related, the experience is much better this time round. When it presents you a card, it has all the LaTeX rendered, and all images showing. Let's see if I don't get sick of it this time round.
In my experience, spaced repetition systems excel when I can create cards that take 10 seconds or less to answer. So they work really well for something like language learning. But it's difficult to reduce mathematical arguments into 10 second chunks．
I agree with you that overly relying on flashcards will take away the intuition, which is critical in fields like mathematics. At the same time, one can use flashcards in addition to other methods. It's not as if using one approach impacts your ability to learn via other approaches. Also, I think one can be clever in how they use them for mathematics. A lot of theorems rely on a certain key trick or two, so I think it makes sense to have flashcards asking what the trick is. I think flashcards are great for memorizing counterexamples, as well. Or heck, even regular examples. Depending on the branch of mathematics, knowing these is immensely helpful (e.g. in analysis).
Having said all that, I'm not using it for math presently.
Can't you just write a card that specifically asks you to give the intuition behind some concept?
E.g. "What's the intuitive interpretation of the gradient of a scalar field, \nabla \phi?" Answer: "\nabla \phi is a vector that points in the direction of greatest increase of \phi."
Weird, why would that be?
EDIT: Well, copy-pasting opens the site but not the article.
I just wish the mobile supermemo version let you export your cards. I left supermemo a year ago for anki because of that - don't want to get locked in when I have thousands of cards.
The windows version apparently does allow exports, but it seems separate from the web version and does not run on Linux.
Seems strangely backward to me. Understanding is my end goal when learning.
Some learning, of course, is by example/exposure rather than by explanation, otherwise you'd never be able to even get started.