Although thats a fine way of pre-inflating the Warrior, not entirely sure why you need to pre-inflate unless you are determined to launch from the side of the window like an LEI.
Here's my Warrior inflation tip :
1. Try to fly the kite
It looks shit and flaps about a bit for about 1-2mins then everything is sorted , beautiful , sweet as etc . . .I've never had to do anything else in light or strong winds.