Everybody seems to think its ok to open 1NT (15/17) with something like:

Some hands just don't fit system too well and I'm considering adding some 15/17 3451(15) 4531(13) etc into my notrump openings. Partner agrees there have been some reverse type hands that we may have overbid and there have been a few that were close to a jump bid and we ended up missing game because of underbidding. The problem hands have invariably been 16/17 with a stiff or void. I would like to experiment with a no trump opening.

I have heard it unlawful to do this. Does anyone know if it is legal to include unbalanced patterns in your notrump range if they don't seem to fit better by reversing or jumping.