Regarding the moosing... I always thought that was caused by coking from the EGR. As in, blow-by gasses deposited carbon in the valve.
And that was true for Tiger (my first V6). Flushing the unit with brake cleaner definitely stopped it...for a while.
But Sally - who doesn't have the EGR system - has started doing it now, at certain revs and very specific temperatures. So I think that the valve-cover breathers are just as guilty, dropping poo in the inlet. I've got an oil change in the near future, and will flush those hoses out at the same time.