If I did practice an art that had solo kata with all these different interpretations, I think I would prefer to practice the kata differently at different times depending on which interpretation I was putting on it at the moment. If the third step in the movement could be either a block or a throw, then I would perform it with one set of body mechanics when I was viewing it as a block and a different set of body mechanics when I was viewing it as a throw. My movement would match my intent.
From previous discussions with kata practitioners, it seems that most don't do this. They seem to stick with a standard "encoded" movement that they can apparently interpret as a bunch of different applications but which wouldn't actually function literally for most of those applications. I wonder why. It seems like matching movement to intent would be a useful exercise.
I completely agree with you. Again, I can't speak for the majority, but you're pretty much spot on, at least in terms of my own approach. I'd much prefer to perform application with a partner, but without a partner, if I want to practice the actual motion of an application, I practice the actual motion of the application as it would be applied, rather than as found in the kata. But that's practicing a kata-derived, two person drill by yourself, not practicing the kata.
However, I wouldn't
change the original kata as I learned it to suit a particular application; that would defeat the usefulness of the kata, which is for me a tool of exploration and experimentation. Once the kata has a single obvious, explicit application, once the movements are less obscured, it becomes too easy to see one way of doing things, and harder to force yourself to see others. Especially when teaching the kata to newer students. If it has one clear use, why use it to find more?
So yes, matching movement to intent is a useful exercise, and I would presume (maybe?) many of us do that. We just don't then feed that specified movement back into the kata. The kata is a thesaurus, the applications, drills, and solo practice of said drills are the things you write with it's help.
Say I'm writing a poem about an apple. It's red, but "red" is boring, so I open March's Thesaurus Dictionary and find the entry "Rubiform. Red in color." I think "Hah, what a great way to describe my apple!" So, I may talk about the apple being "rubiform" in my poem. I may begin to use the word "rubiform" in conversation, and I may find I like it, or I may find it's too cumbersome and requires too much explanation.
But, even if I decide that talking to people and using the term "rubiform" is going to be a permanent part of my vocabulary, I'm not going to cross out the entry in March's, and replace it with a handwritten, "rubiform. Red like an apple." Now I've changed the meaning, and everyone who looks up Redness-Greeness in my particular copy, will see that "rubiform" pertains to apples, and they'll use it as such, overlooking that it's actually a more general term for redness. I myself might start using rubiform to mean only the redness of apples.
But yeah, I would say it's obvious that if you want to practice posturing and breaking a full nelson, practice posturing and breaking a full nelson, don't practice Bassai Dai.