Often, when I'm studying, I'll find a word that I don't know very well coming up pretty regularly, sometimes every couple minutes. After a few iterations, I can usually nail it the next time, but since it's such a short-term recall, I don't trust my knowledge of it yet, so I usually mark it as so-so/2/yellow. By doing this, am I A) wasting my time or B) potentially messing up the SRS algorithm by causing oversaturation of the character/word, or should I stick to this method for optimum acquisition of new words?