At killing organisms, probably. But then it may no longer be a no rinse sanitizer
Yep. At NHC I was talking to Jim from Five Star and told him I mixed it stronger to get the pH down. He said that at stronger concentrations it's no longer no rinse.
Because of flavor issues or pH issues? Seems like any remaining volume would still be diluted out so much that it would have a negligible affect on the pH of your final volume of beer in the fermentation vessel.
So at what mixture do I need to be concerned?