As we learn, we build habits.
Some help us play better.
Some hinder us.
When we try to learn a new habit (ie "Break an Old Habit"), there is, essentially a battle going on in our minds. The new habit (an alternate position or keeping the throat relaxed) is like a young plant that needs constant nourishment and love.
Without constant, nourishing vigilance, the old habit will reassert itself. When our attention is full, dealing with musical complexity, that's when the dominant habit, lurking in the background, can take over again.I wrote about something similar in an older blog post: Taliban Habits.
We want our new habit to grow into a mighty oak!
In order to do that, we need CONSTANT VIGILANCE.
While the new habit grows, we have to make sure the old habit doesn't rise up and reassert itself. This, I think, is one of the great benefits of playing simple tunes or exercises. It frees up our brains to make sure the new habit grows.
Otherwise, that precious little sapling gets cut down by Darth Maul!
(or something like that...I know it's a mixed metaphor)