A few articles by
Khatzumoto and a couple of blog posts by
Steve Kaufmann have gotten me thinking more about using an SRS for language learning. My specific use of it right now is for reading, but I think these concepts apply to language aquisition overall.
(1) I think it is important to use an SRS not as a memorization tool, but rather as a way to "make the brain more attentive", as Steve Kaufmann often says. An SRS should be used simply to provide multiple opportunities to see a certain phrase or sentence again-and-again so we have more chances to think about the words, patterns, and meanings captured in that item. Nothing more, nothing less.
(2) Daily use, if possible, is ideal but it also needs to be a periphery habit. 5 minutes here, 10 minutes there. That is good enough. Use it to fill in the gaps between the time you are working with primary materials (books, articles, listening, etc.)
(3) You should not pressure yourself with the SRS. If you keep forgetting an item, who cares? You will get it eventually. If you just don't like a particular item, go ahead and delete it. You should attempt to SRS for probably at least 25 minutes everyday but not much more than that. If you miss a day or two here and there, no worries.
(4) About 20 sentences/phrases a day is equal to roughly 600 items a month. That's about 7,200 a year. 30 a day is just over 10,000 in a year.
(5) Just be a monster with the input collection. Get most of your stuff from the Internet where you can copy and paste easily. If you don't want to spend huge amounts of time trying to fill in the back, leave it blank for now and maybe you will fill it in later. Again, no pressure and no worries.