Good question. The high and low in T levels are probably based on a lot of variables like a mans biological break down of esters, the amount being injected, time between injections and the the type of T being injected...among a host of other things I am sure.
In Ken's case, in my opinion, one weekly 240 mg injection is a lot at one time and can be a cause of increased E2 fluctuations plus things like he feels between injections. The peaks and valleys can make him feel great one day and shit the next.