Measured move projections are, in my opinion, more art than science. He also talks a lot about probability, and the inverse relationship between probability and risk: a low risk trade has a lower probability of success. The further the stop, with appropriate money management, the greater the likelihood of avoiding a premature stop out and having a successful trade.
From what I was told in another thread - he basically makes up these probabilities and does not actually calculate them based on hard data.
There is just too much human interpretation involved. I am now trying to use various indicators to approximate his steps. Some of the attempts have been successful, and some are still works in progress. I have been able to directly apply some of the price action concepts into algorithms.
This is a huge weakness with these type of methods as you've already discovered. Not only does the interpretation vary between two traders, it will quite likely vary if the same trader views a chart today and then views it again tomorrow.
I think you're doing the right thing trying to systemize this stuff.
Al does things the way he has learned over his 30 years of experience. It works for him, and if you have the right personality, you might learn a great deal from him, as I did.
And you're sure it actually does work for him...?