Well, I don't know about "learn" learn, but... well, for one, children are supposed to learn like 10 new words a day, and in Mnemosyne (flashcards) the daily limit (not a hard one, more of a suggestion) for new cards is 15 (which, with a lot of experience, makes quite a bit of sense to me)... Yeah, that doesn't compute.

I mean, well, I - having also been reading articles - have read that there's two sides to both cramming and steady study. With just cramming stuff like crazy you remember more in the short term (but quickly forget), whereas with spaced repetition information persists longer, but it doesn't come up so easily in the short term... That is all to say, I can see a scenario with 400 words a week, just not very... interesting, I would say.

I however... don't even know, either short term or long term goals with Welsh... I mean, what kind of writing ability can I expect if I don't have anything to read for practice... I actually just thought I'd complete a single textbook and call that an interesting linguistic adventure. But the situation with textbooks isn't accommodating. Well, at least with the kind which would make that journey in some way satisfying (like, 400 pages).

But speaking of practice, I've already mentioned that I write in a diary in Polish. Well, one thing you could adopt from that, with you new-found number wisdom, is writing out dates in German... It might be more of a challenge than it sounds. At least in Polish it took me 4 months of everyday practice to finally remember the names of the months (although Polish has its completely native names, as opposed to Roman-based in German).