Louie, it sounds more like the key is to define exactly when a line change, speed change, release change, or whatever is actually necessary to search for a better line. For me, I don't like to make a change based on one shot only, since the result of a single shot can be misleading. I'll try a line for a couple of shots, making sure that I feel comfortable that I made a decent shot, before deciding to look for something better. I know that I find some nights where I'm pinging 4's, 7's, and 10's, all from the same basic line....in a case such as this, any adjustment might be counterproductive.
I guess what I'm getting at is to find a better way to determine exactly when is a good time to make a change, rather than making a change based purely on one shot. I would suggest that you try what you are doing for at least a couple of frames before giving up, unless the results are blatantly obvious. However, I bowl in a house where small adjustments make for a big change in reaction (when playing on the fringe of the heavier oil), so I make minor changes instead of major changes.