SAK is very profitable ,thats why we're mining it

imho talking about SAK profitability makes sense when you can find at least 1 block per hour,
until then it's a waste of hashes
Statistically speaking, no.
this is multialgo autoswitching pool,
just because of that too fast coins as well as too rare blocks aren't welcome
Again, statistically it doesn't matter, it's just an issue with people that want to always get paid even for small periods of time.
If a coin is profitable, it still is regardless of difficulty.