If I am going to go into writing about a controller then as a courtesy more than anything, I will let him or her know before I leave the frequency. Nothing to do with willy waving but purely as a 'heads-up' for the controller, so that they can collate their thoughts when they unplug and if allowed, then it gives them the chance to listen to the tapes whilst everything is still fresh in their mind. When the subsequent email or phone call comes asking for more information, they will at least be prepared for it.
I would have perhaps have worded it differently to how my fellow Irishman did but that is easy for me to say in hindsight. I did think he showed more restraint than many others would though.
There is no place for emotion on the R/T, regardless of where you are are in the world. Keep it concise and operationally relevant or otherwise keep quiet and don't say it.