I always cleaned the frames the old way. Changed to wfp 3 months ago, a friend said avoid touching the frames because it just activates the dirt which will come running onto the window after you've gone. And I've read loads on here from guys saying the same thing.
So I tried when I started, to avoid the frames, just getting into the corners. But it quickly started to irritate me, I kept thinking why? Surely if you give all the frames a good clean, every time, eventually you just have to get spot free windows.
So I clean the frames as thoroughly as I can every time, the glass seems to be coming up better, easier every time as a result, and no dirty frames to worry about.
The old adage surely doesn't change: "If a job is worth doing, it's worth doing well!"
Pj