The primary fuel screen is clean and flowing nicely, which also frustrates me in that if the spin on or secondary is clogging, how did it get past the primary, unless of course we are talking about fine particulate contamination obviously sub 100 micron sized particles will flow through the screen and not the filter.

With regard to catalyst being clogged, and I don't doubt it could be, I would think the cold to warm transition in operation temperature and improvement in performance, i would guess that an exhaust restriction issue change regardless of operating temp but fuel would as a cold engine requires more fuel than a warm one, no?? Also, is the catalyst a "burn clean" device as the trap was?