I used to do the same thing when I had my Inter 20, sailing it alone in up to 17 knots here on the lake. Sometimes I would just trim the jib and ease the main quite a bit, traveler out, boards up a bit, and had no trouble keeping it under control.

I first tried it with main only but my mast was raked so much I found it had far too much weather helm. It was actually easier to control it with the jib on than without.

But as you pointed out, the mast rake on the Blade is not so much, so there isn't much helm change at all going from jib to no-jib.