Just found this thread looking for a similar thread.. am working on a 25fps pal project and needed to move my video to sync less than a frame in movement.
My fix:
copy everything in the sequence
start a new sequence at 50fps (or 59.94 if in ntsc)
paste everything into the sequence
make your minor adjustment
copy everything
go back to your original project
paste
fingers crossed the sync will be spot on.. worked for me on one project so far, will have a few more to do