You'd certainly have a case if someone who had never been fishing before thought they could become an angling guide after a week. But let's test your theory a little.
I've been a fisherman for nearly 50 years. I've been a fly fisherman for 44 years. I've fished extensively for trout, grayling, sea trout and salmon in streams, rivers, chalkstreams, lakes, resevoirs, tarns, loughs burns and lochs. I've fished in Eire, Wales, England, Scotland, Norway, Russia and the US. Additionally, I've salt water gamefished with fly in some nice and hot places. I'm not going to begin to cover coarse fishing or sea fishing but it adds different perspectives. As previously mentioned, I did a reasonable amount of gillieing when younger.
I'm hoping to partially retire in 5 years. Say I want to be a guide. If I went on this course I might learn anything form a lot to nothing new. I'll keep an open mind on that. But to test your theory do you think I'd be able to call myself a guide or even a provisional guide at the end of it?
Oh and all the ney sayers are missing the most obvious reason why you might want to go on this course apart from Caeran's very sensible assessment.
With all due respect, if you have spent a lifetime fishing like you and I did, the day I would pay 2.5 K for a week learning to tie knots, to recognise what flies around and to help someone with less experience, I'd go for a voluntary lobotomy. Then perhaps I still might learn a thing or two about what I've been doing. Nothing personal and the thought alone of becoming "afraid" of the load of new guides that is going to inundate us is quite comical, to say the least.