What is a street chump? Is it a BJJ blackbelt who is ****ed off because he got screwed by the referee in his championship match that morning? Is it a 275 lb collegiate lineman who is on cycle and having a bit of roid rage? It it the guy recently out of prison carrying a blade who has just done a few hits of PCP. Assuming someone on the street is an easy mark shows your lack of street experience.
I've been doing submission grappling BJJ tourneys for years now, as well as following many of the tourneys that I haven't competed in. I can count on one hand the number of standing locks I've seen in thousands of matches over the years.
As far as using a joint manipulation, such as a kimura, to effect a throw, those work fine, but we are talking about standing control, not takedowns.
Training standing locks is generally a huge waste of time, right along there with those FMA disarms you were talking about.