Just a theory......
Perhaps Ron Tracey was promoted up top when Starfleet Command saw the OMEGA GLORY rushes, then noticed that moment for moment, he completely trounced Kirk's patented fighting moves. And clearly enjoyed doing it.
However, I think are being too hard on poor Commodore Decker. Aside from some overacting and teeth-gnashing in the shuttle, William Windom treated us to perhaps the finest guest star performance on the classic run. And definitely the stubbliest.
All right, he endangered the ENTERPRISE in act three. But Kirk only resents that because he's not doing the endangering. Decker was assisting the CONSTELLATION. This is called teamwork. For James T. ''Obsession'' not to realize this is quite the Crite hypo.