You want to see it lifting... if it actually all bubbles and comes off easy you could blast it off... But I hope you don't have neighbours...
If it doesn't lift totally even.. you will want to putty knife it off and slap the stripper/paint mess back down over spots that are stubborn and leave them again. In many cases this will lift those as well. If you blast it with the washer... you neutralize any stripping action and at $50 a gallon, I wouldn't be doing that.