I'll be happy when Webb admits to his pharmaceutical use during 2007; he ran with a heavy heart of guilt thereafter...
I've also seen more than one person completely smash their old PRs after getting dumped.
I'm one such person -- 80 second PR for 8k XC.
Nothing could be further from the truth.
Highest Testosterone release came from periodic bouts of abstinence during training followed by periodic sex in men. Numerous studies have pointed this out. Also abstinence is followed rigorously by both boxers and sprinters before a fight or race.
Testosterone release peaked during sex before dropping off significantly after several days.
Elite women showed similar patterns however the sample size is considerably smaller and the risk/reward to abstinence lower also. It should be noted that many female athletic programs have used induced early term abortions to increase hormone levels and improve training performance.
Alan Webb is not really reliable on this topic based on both his up/down performances and his event.
If anything sex should be used purely as recovery from a training stint.