Eh? So you are saying that LSJC is about receiving information are you?I think developing Lsjc in chi sau is, as wingchunIan notes, to use "[...] the information that your arms receive upon contact to find angles and gaps".
Jesus! LSJC has nothing to do with rattan circles!However, I feel the idea of Lsjc and the rattan cane are perhaps more relevant to developing fighting skills through chi sau.
Poppy****!Yes, you can feel for a gap but you don't process that information through your mind; that forward intent is already there so that when the linchpin is removed, your strike is already on its way.
LSJC is an important part of Ving Tsun. It's not hard to develop if the training methods are correct unless the student is a bit useless. maintaining it in sparring is another story. I never even heard of LSJC in the Ip Chun lineage.I must add that lsjc, for me at least, has been hard to develop; particularly the subtleties and balance so that your opponent cannot use that intent against you. I will also add that, at least through the Ip Chun lineage I initially trained through, lsjc is not something trained very often nor is it, much to my frustration, a concept made explicit to students.
LSJC has been roughly translated to "loss of contact, thrust forward without hesitation". People wrongly assume that the "loss of contact" bit means that we already have arm contact and when it is released we should thrust forward using some kind of springy energy. That is a common misconception in Wing Chun.