The task ahead has got a little bit clearer now.
I need to learn how to read from chord symbols. I should carry written sequences around with me and work on them in my head. Yes, that’s a good idea. I could photocopy a few from the Real Book and carry them around with me. I don’t necessarily have to have the instrument with me.
I think I need to learn to “see” each chord symbol as a harmony flavour and a scale – sort of a grid of possibilities within that flavour. Having learned that then I should learn how to imagine how the following one sounds while I am still playing the first. I think this ability must take a long time and a lot of work to acquire – and the method of acquiring this skill must be efficient.
Working out methods is where I am right now.