The tight reg who flats your c-bet on the flop and then leads the turn is not bluffing. They have two pair or better, or they just made their draw. Either way you're usually drawing thin.

Why they do it

Tight regs at $1/$2 don't float and then lead as a bluff. That's a move that requires a lot of confidence and balance they don't have or don't need against this field. When they come alive on the turn after flatting the flop, they got there or they were already there.

The adjustment

Fold one-pair hands. Call or raise only when you have two pair or better or a strong draw with fold equity. Don't try to "find out where you're at" with a raise - you already know.

What it's worth

Calling a tight reg's turn lead with top pair costs you the turn call plus the river when they barrel again. That's $80-150 in avoidable losses per occurrence.