Again, there are some great pithy sarcastic comebacks like "capirai" in English, too, but your context for a catchall expression like this is too narrow.
More context: it means that it's taken for granted what was said before, because the character that spoke earlier has a very strong identity and we can almost predict what his answer will be like. Grazie Simonetta
We never got context for this one from 2005 but I was wondering how about "yeah, right.....big deal!" in the sense of what you are saying is obvious and there are many aspects you underestimate or don't mention..... I don't have a specific context myself but I hear the expression frequently in spoken Italian and wondered if we could find a good rendering for most times... Are there any native Italians who can confirm if I have got the gist of "capirai...." Jelsah