I think our guy is maybe just using the wrong word. What he says is 'bounce up a few inches', and I think he probably means the same as you when you say 'slight release of stretch'. The bad kind of stretch, what your first link calls 'ballistic', would be bouncing down. But because of the 'bounce' in his description, people might do that anyway. :( I like your way of describing it much better, it is clearer and safer.