Is exactly as you said ... St L Kick to Hien Shippuu kyaku must be LK neutral or keep the jostyc back (after to complete the charge) and then so quickly as you can ... move forward and K .... it isn't a easy move ... in frames language you only have 9 or 10 frame before the charge expires.. I'll try to make a tutorial about Neutral hits within charges move in a future.. but meanwhile I leave you this to get a better understanding of what I'm trying to say kzfaq.info/get/bejne/ipmpgcyL163WkaM.html

@@KWill7 I asked because I had no problems doing the Hien after f. L. Kick, but couldn't do it after st. L. Kick. So I thought there must be some kind of "exploit", but as you say, it's just hard to do. Thanks, for the answer!