I think the rational (mostly linguistic) parts of our brain can influence decisions made by other parts, if we're smart about it. The main trap seems to be that when the conscious and subconscious parts of our brain disagree, we may decide that we didn't will hard enough. So we try to "will harder", which to the linguistic part of our brain means sticking the word "very" in front of everything and generating a bunch of negative self views, which has the opposite of the desired effect on our subconscious.

IAWY; it's either the opposite effect, or just no effect. You could also think of this as being a case of "the leader not listening to subordinates", in that the "try harder" mode is ignoring whatever the actual problem is -- i.e., the subconscious goal or prediction that's interfering. In my experience it's much more important to teach people to be able to listen to themselves (i.e., become aware of what they already believe/expect/desire) than to talk to themselves (i.e., push new information in).