Digital BW, The Print

Paul Roark, you mentioned a "wiper blade" whose condition might cause
  some MIS clogs on 2200.

Where is the wiper blade? I've never seen it mentioned before. 

Can you link an online diagram that shows this?

1280 experience seems irrelevant because that printer's nozzles were
designed from the beginning for "ink" particles like MIS's, not for
pigments (2200 and newer) and despite that were famous for clogging
even with the Epson ink, whereas 2200 nozzles are much finer and in my
experience are more than 99% reliable with OEM (essentially never
clogs with Epson pigment no matter how long mine has sat unused). 

If I had the time to refill carts I might prefer to re-establish my
wet darkroom, currently gathering dust in storage. I"ve seen some
extraordinary new silver prints recently. I'd have to find some space,
however :-(
 
Presumably my best answer will be 3800 when I get my photography to a
meaningful enough level to justify large prints (3800 will be an
antique by then!).

I've found ammonia on the pad to be helpful minimizing the severity of
clogs, used every few months, but not helpful to prevent regular minor
clogs. 

The cost of cleaning carts appears superficially about the same as
relying on unclog cycles. Has that proven correct in practice? Do you
use cleaning carts as routine maintainance, with or without clogs?