I don’t agree with you guys. Some systems will automatically decide that you got it right so you know it. But better ones like Anki let you choose how firmly you know it and you can always lie and say that you didn’t get it right.
As far as thinking about what mnemonic you used, I’ve never found that to be a useful expenditure of time. I’m sure opinions will differ on this, but the mnemonicis for putting things in. I’ll create a new one each and every time I get a word wrong if need be. Worst case I wind up with more connections that I really need.
It really sounds like less of an SRS problem and more of a “you guys don’t trust the system” problem. Which is fine, to an extent this is a personal decision, but with the number of flashcards you need to cover even a children’s movie, I just don’t think it’s worth worrying about the times when it falsely pushes the card too far down the stack. If it does that, the card eventually pops up again and you fail it and it comes again more frequently. What’s more, people are almost completely incapable of completely forgetting something once its been stored. So, you might not remember that word now, but if you hear it or something that reminds you of it, it’s likely still in there somewhere.
As far as rote learning goes, SRS isn’t rote learning. People can use it to engage in rote learning in a more efficient fashion, but SRS doesn’t deal with the mechanism of memory, just the mechanism by which you’re presented with the cards. I don’t personally see any good reason why I should spend time reviewing cards that I’ve already learned every time I want to review and SRS helps me a lot with that.
As for the size of my decks, they tend to be rather large. The one I’m working on for the HSK exam is about 5k cards and the one that I’ve been using for Finding Nemo is probably only 1k cards and the other deck is probably only another 400 or so words. Apart from the HSK one that takes longer because it’s on Memrise, I don’t spend more than about half the time you do and I can easily do it while I wait for the bus or while I’m riding home. So, in practical terms, I spend no real time on it.
As far as review goes, 45 minutes a day to review 420 cards is to me an unnaceptably large amount of time to be spending on reviewing cards that you’re supposed to already know. That’s time that you don’t have available for things that are actually going to improve your language skills. If you know 98% of the words, that’s a pretty clear indicator that the material is too easy and that most of those cards should have been swapped out in favor of new materials. 80-90% is a better target success rate as it actually represents the fact that you haven’t completely solidified all the vocab. Just as long as the cards you get wrong aren’t always the same.
As far as how many words to be fluent, it’s not 15k or 20k or 100k, fluency has very little to do with the number of words you know. Fluency is partially a function of vocabulary, but it’s really a matter of how you use the words and grammatical strucures you know to communicate meaning. There’s no guarantee that you’ll be fluent because you know X words.