Actually I worded my last statement incorrectly. I really should have said that you should take your blinders off and have a more open minded approach as you started this discussion with a terse statement that he is just a Yank. We see the unit flashes and we see the USA badge, fair enough, but you fall into the trap that every person who, with little or no experience in the military falls into in that you deal in absolutes with no grey area. For sure, this guy could be an American in the Canadian Army who for whatever reason has ended up in the Film and Photo Unit, interesting and I can live with it even though he is as old as the hills and dresses like a slob.
What I am saying is there could more to this, Film and Photo was a pretty specialized unit who worked in the PR world, perhaps this guy is an American working for the Canadians and he has been given a uniform for this purpose. Why you seem to feel that that is no possible way this person is not an American, a reporter or a technician or whatever working for Film and Photo baffles, but does not surprise me due to your other ‘absolute’ statements.
Obviously the caption to this photograph has deepened the mystery even more and recorded this fellow as a Private which is interesting but not conclusive with an investigation into his service record being the next step.
Dress regulations are guidelines on how everyone in the military should establish some form of uniformity. They in themselves although worded as absolute are not and many grey areas exist especially within the 'tribalism' of the Canadian Army. How dress regulations are interpreted and enforced can vary widely and again, if this fellow is a member of the Canadian Army and dresses that poorly is certainly an example of how one can slip through the cracks (or how lucky he is to not get picked up). By no means were dress regulations ignored completely, and to state as you did earlier on in the discussion that by 1945 the regulations were ignored is a blanket statement with no merit.
You also state, “If seconded or attached from the US Army because of a particular skill or as some sort of liaison, he would likely continue to wear his US uniform”. Well who is to say this fellow is in the US military, perhaps he is a civilian in the employ of Film and Photo or a correspondent and that the uniform has been provided by the Canadian Army for him to wear while doing his job. I think Clive nailed it on the head with his thoughts on this earlier on in the thread and will leave it at that.
It is obvious our opinions and methodology do not mesh, that is fine, I know that I can certainly agree to disagree.