Andy,
I've now moved the filing system and forms on to my PC and photoread Windows Explorer before I start a session, hence why I've been using a computer filing system as a visual model. However, I'll try using filing cabinets as well.
What's pre-mind mapping?
I have noticed 1 improvement already but not in the activation step.
I've found that when I prepare, the tangerine technique works much better that before. I'm not too sure why yet, although I suspect that as I've photoread the filing system, that has acted as a kind of 'session preparation' so when I prepare to photoread a particular book, I'm already in the zone 
I'm conducting my first activation session using the above tweaks today, so I'll post on this thread if I notice anything...