Yup. I made the mistake of coating hundreds of feet of baseboard with
Deft Sanding Sealer before I'd realized that's not the proper sealer
under poly. I went ahead with the poly top coats and haven't had any
problems. Would I recommend using it under poly? NO.

Dave

C & M wrote:

I picked up a can of Deft sanding sealer and didn't read it until I got it
home. By the sounds of this stuff it's a laquer base so that would make it
incompatible with MinWax polyurethane, right?