Top question: Yes. What you are describing as a perpendicular/orthogonal force component on the barrel is a fairly sudden and abrupt force.
Bottom question: Let's imagine Bonds' swing ... something we've all seen often enough. When Bonds tips his barrel, he also lowers his hands .... and when Bonds untips his barrel, he raises his hands. Extensor action will occur during the untip (raising of the hands). Watch the barrel and you will see the transition.
Okay. Good to know that I finally understand the concept.
Where does "extensor action" happen with Mig? I'm not seeing pre-launch 'along' forces happening.