I give up. I have been trying to find an article I read in the New York Times a few weeks ago and have google-d just about every combination I can think of, to no avail. Maybe some one saw it--it was about building new neural networks in the brain by training yourself to do new things. The article mentioned a Japanese practice of doing routine tasks differently every time so that you were aware of the process and not just "going thru the motions." Let me know if you recognize either this Japanese term, or the article.
Anyway, I can't post a link, but I still want to discuss the idea of creating awareness just by doing things differently. We do it all the time in yoga in subtle ways; recrossing legs, using different spacing, lifting heels, turning in toes, etc. All these little adjustments shift which muscles are working and draw your attention deeper into the body. My favorite way to "startle" students is to just have them re-cross their fingers in Hastasana (Overhead Arm Stretch), so that the other index finger is on top. It always feels massively wrong, and I always feel like I have an extra finger all of a sudden--and yet I'm simply interlacing fingers differently.
You can start to think of all sorts of ways to shake up a yoga routine...Down Dog with toes turned inward, using different mudras (check out Yoga Dogs and Chocolate for more on these hand positions) in Sukhasana, coming into standing poses differently (jumping instead of stepping the feet apart, or vice versa), doing a Sun Salute veerrryy slooowwwly or quickly, the list goes on and on.
I think the article was about how the brain will be more nimble if you force it to "think" about routine activities instead of just shuffling through them blindly. Developing muscle memory is good, but introducing new ways to stretch is also good for developing strength and flexibility. Especially if you want to keep the gray matter fresh...
Let me know if this rings any bells!