All this was and is taught in Iwama. Find yourself an Iwama teacher and you will have your questions answered in considerable detail.
Regarding your second point, I belive that you need to learn how to crawl before you can run. Perhaps yours is a different methodology. Can you please tell me you aikido lineage?
At least Saito senseis interpretation of these facts are taught. Details on these things can vary between Iwama-style teachers as well.