I have taught literally thousands of people to spey cast albeit at very differing levels from group demonstrations right through to long term regular one to one level.
The results of my endeavours have been mixed no matter how hard I have tried. Bear in mind your average fly casting instructor will generally see far more people who are struggling and cant seem to get it than very talented casters maybe aspiring to be an instructor themselves. Why have I struggled to always get the results I wanted? well sometimes people just dont have the patience or determination to succeed and they give up too easily, other times they cant afford to pay for regular lessons or choose not to, occasionally they are just guys better suited to spinning, we cant all be good at everything. Something that has always been clear is the more a pupil would visit me the better they would become because you cant learn everything in a 2hr lesson.
What I have absolutely no doubt about though is that whenever someone is struggling regardless of their level its usually because the dont really understand in a clear way what exactly they are trying to do and why they need to learn to become good at the basics which I will show them. Simple things like line tension, correct alignment to their target, appropriate timing, correct rod angles and observing the results of your actions. Its true you cant see yourself unless to go to the trouble of filming or use advice like I would give of looking at yourself in a mirror or your reflection in your patio doors etc, watching yourself is a real good way to see what your doing right and wrong so long as you have been show what is right and needs to be practised.
I remember a chap who couldnt get the rod back behind him at the appropriate angle of 45 degrees, he barely went past the vertical so I put him in the right position, gave his some reference points to repeat the position and took a photo of him in the right position which I sent him. I then asked him each evening to spend 20 min in front of the mirror adopting the correct position, once in the right position getting him close his eyes and get a feel for it then drop the rod down and repeat. Laterly adopting the position with his eyes closed and then opening them and see if he was there. Next time I saw him his position was perfect, felt natural to him and had became ingrained in 2 weeks, this allowed us to move on to his next problem because problems need to be fixed in an order. If this guy wasn't committed to his training he wouldn't have progressed as quickly as he did.
It is possible to learn from books, videos and demonstrations at Game Fairs etc but only so many of us will progress well that way, the truth is regular 1-2-1 tuition and then practise is the main way anyone will make good progress in a reasonably short space of time but this will cost you money.
I was once the subject of a magazine article where the editor asked the question 'why do salmon fishers spend so much money on fishing and so little on tuition'? something Ive always pondered to myself.
Here is a very simple example of something I see all the time, anchor placement on a single spey. So many people dont know where it should be, thats a very easy one to establish with a very simple foolproof method that isnt hard to remember. So then after that its a case of landing it in the right place consistently, I can then help them to do that but the number of times I would ask a pupil there that last anchor landed and they look at me with a blank expression of not knowing is amazing. When questioned as to why they didnt know they would be quick to answer 'well I wasnt looking', ok so do you think looking to spot your anchor might be beneficial? then the smile comes as the penny drops...
Ive seen this so many times its quite amazing.
If anyone wants to learn then go see an instructor with a good reputation and dont be star struck or afraid of them, if you dont understand then ask them to explain in a different way until you do. Unfortunately like all other things in life all instructors aren't as good as each other so best try and find one who someone who comes recommend and sadly its also not a case of getting what you paid for.