I guess I simply don't get it. I go with imperial evidence. I trained aikido for years and TKD for almost a decade, yet I could not leverage it against a bjj white belt with 3 months training. So I guess bjj students train to deal with TKD and aikido movements?
Either that or their training strategies simply work. I'm not a religious man, so I'm going with evidence over faith.
It's more that TKD and Aikido have no resistive strategies to deal with BJJ in the same way that, as you yourself, stated BJJ has no resistive strategies to deal with stand up Judo.
Right, back to the party.