I find the minimum requirement on edits is fairly aggravating. Below: Reasons why, and a possible method of alleviating the problem.
Firstly: because there may only be a few characters wrong, it is odd to force me to change other, subjective parts of the post to be able to correct the blatant error(s). E.g., someone mis-spelling “etc.” as “ect” in an otherwise fine post.
Secondly: The error message is obnoxious. “Oops,” it starts. “Oops”? I sure didn’t “oops.” I was correcting an “oops.” If someone should be saying “oops,” it should be the system, for preventing my correction from taking.
Thirdly: This policy discourages me and, I must assume, others from making edits. Is that really the intention of this policy?
Lastly: I’m guessing the reason for this policy is to prevent moderators from becoming bored by approving tiny edits. If that is the case, perhaps a better solution would be a streamlined, inline, character-level diff view… perhaps show a whole screen of extremely short edits for approval as a series of one-line highlights. Like a Gmail inbox of tiny edits. Check, check, check (or select all & uncheck some), approve, done. Then the negative consequences above are avoided. Result: Happy mods and a better-written Q&A corpus.