5 years on and i still do the walk sometimes, conditions here are quite challenging though

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Best thing i did was find a large patch of knee deep water without chop and master it there.
After that it was all down to conditions, which are pretty crap here all year.
If you need a little bit more power out of the kite keep swaying it gently up and down.
if you need a lot more power drive that thing UP DoWN UP DOWN UP DOWN!
to answer the original question, i nearly had it after about 15-20 sessions on the ol' X3, but 1 decent session on the flat water with smooth wind and it all came together, had to go downwind to land it where i started.