not on Dysons, but...
...bristles of floor brushes are on my list as well as combo nozzle roller axles and belts of power brushes.
I have never owned a Dyson nor will I ever do, but what comes to regular vacuum maintenance, I like to give the brush frames of a floor brush or of a combination nozzle a thorough combing: Hair, fluff and carpet fibers seem to have a tendency to knead down into those brushes. I flip them to "floor mode" and hold those brushes very close to a running power brush to get all that debris combed out and sucked up.
Likewise, the roller shafts of nozzles of all kinds get their regular scissors-cut-down-and-off so they can rotate freely. (Which applies to brush rollers as well). In former days I used to just pull hair and threads out of them, but I have changed: I cut them with scissors, so once sucked up, they won't wind around the roller axles again for being too short for that. Works fine.
Disassembling? No. Just in case of "sick cat puke-out" hazards. Normally not.
To get rid of residues getting stuck on the blades of a direct air vacuum, I run a cup of coarsly shred rice grains through the machine, that will do for the major part of it.
Washing bags? Here and there, depends on model, make and incident.
Reselling a vacuum? Yes, always! My vacs go out only when done as good as one can go. (My own pride, not necessarily to be applied to others). Only washed and dried out and polished.
Having disassembled a vac for other reasons? Yes, always washing and polishing (once I am at it, I can do a complete job as well, can't I?)
Who is with me? Spring time is a good season, the wind and the new sunshine will help you dry out washed hoses on the clothes line in no time.
Cheers
J.