For everyone with Trans issues - tried cleaning the valve assembly?

[flatlander]

I've seen many posts that talk about changing the transmission fluid, but I haven't seen anyone discuss how to clean out the passages of the trans valve assembly. Has anyone done this? The valve assembly seems pretty vital to controlling the behavior of the transmission. It has many small passageways that could get fouled up. I don't think a regular fluid change would flush out these passages and restrictors.

My friend recently has his Jaguar's ZF trans acting funny; staying stuck in gears, hard downshifts, "rear end bang"... behavior that had been reported on our X5 transmissions. He opened the valve body and found that the passages we being choked by the 'dirt' in the fluid. A regular trans flush/fill would not have cleared this out.

Keep in mind, this is not the exact same transmission. However, the photos show a representation of what's inside our trans.
Pics attached: