F3G,
A very very good post (the long one). Most insightful
One little thing in the short post:
As Urusla Le Guin once said, "If it ain't broke, don't fix it and if it is broke and you don't know how to fix it, don't fix it."
We have to push boundaries though. If something is working well for a while it does generally pay in the long run to try to 'optimise'...not always though. Trouble is that it is not possible to know one way or the other until tinkering is complete