This is exactly what I was talking about in an earlier post. Now, a new student should absolutely be trying to replicate exactly. They won't be able to, they'll actually suck at replication, but they need to stay focused on that. Once you can replicate reasonably well, though, it's time to explore within a form or technique.I agree with this but it took me quite a few years and many different dojangs and instructors to come to this realization.
I have completed 9 full moves in the last 21 years and every time it has been a distance of at least 500 miles, but usually more around 1,000-7,000 miles, and each time I had to find a new dojang to train in once I arrived in the new city/State/Country..
I see a lot of the students (and Masters) of my original school, which I still really love and keep in contact with, devotedly trying to all do each technique and pooomsae EXACTLY the same.
I really think that this is not best. I think that it is okay to "evolve" (might sound pretentious but that's the best word I can come up with) some techniques over time and especially I find that I like to alter the rhythm and pace of some of the poomsae.
In my opinion, too many schools are too worried about making sure that every student does every technique/poomsae exactly the same way every time.
I am not advocating for a beginner to branch out on her/his own and not listen to their instructor, but I think that it is natural, after 10 or 20+ years, that instructors will start to change a bit and have their own "flavor" to their techniques.
I've gone so far as to teach differently with forms. The short forms ("Classical Forms", 2-man forms) I was taught were quite precise. Angles were always the same, exactly the same stance, ending hand positions were exact, etc. I did away with most of that. I want to see adjustment for stiff knees, height differences, etc., since that's the kind of adaptation I'd expect to see in application. I then added long forms (no partner) to allow them to practice exact moves. Once they know the form, I encourage them to alter the form: try different angles, do it slower/faster, do it more smoothly/abruptly, do it with complete ease/with strength. Eventually, I'd even want to see them scramble the long form, recombining the techniques to practice a sequence that actually helps them. If I ever manage to develop a few instructors, I'm hoping they decide some of my forms are crap and make something that works better. Heck, I'd be happy to steal a form from an advanced student and make it part of my curriculum.
When folks try to replicate something exactly (like the folks you mention who keep the poomsae static), they're assuming what is there is more or less perfect. And that's a problem. It leads people to a dogmatic view of their art. They start to say things like, "We don't kick that way in X style. It's not how it's done," rather than rejecting the kick on a principle: "We don't kick that way in X style, because it exposes you to ____."