I think whips are more of a turn and flick which naturally sorts itself out as you move forward provided you point your bars in the right direction at somepoint, whereas a 360 isn't really a natural rotation. Apparently backflips are much easier to do (not that I know from personal experience either though!)
im almost scared to see danny hart do a knack. i feel like the bike would jump out of the screen and hit me in the face! i leaned back a little when i saw this piece of steez