I'm repairing large sections of old T&G flooring. My problem is I must work from the groove side and don't know if blind nailing is possible. Any suggestions?

Not sure what the conditions are, but one thing to look at is to use a spline and install the first row with grove to grove orientation. Then you have normal install for the remaining.

Great idea, thanks a bunch! Can you purchase spline or do most people just mill at the job site?