So...
PE6: spent almost one year to master it, went through infinite frustrating reiterations of the last microcycle over and over again, even testing mastery was quite a pain.
PE7: a single microcycle spent, just tested mastery today, passed with not many issue (a bit of pain at the last reps of fifth set), will repeat in some day, but looks totally possible.
I know the method is not linear, but... wow. I'm amazed!