Thank you, NYC1956! I'd looks at my reference library, and found SOME of that information, but far from all of it!
---A partial list (summary of not quite all subclasses) of which Hudsons were built with which feed water heaters is in Stauffer's "New York Central: Later Power." (Note that type of feed water heater DOES not correlate with the NYC's subclass letters: J1b, for example, war buit with both Elesco and Coffin.)
---Photos in Stauffer's "Thoroughbreds" had confirmed, what TCurtin suspected, that many applications of Worthington's were retrofits: most of the photos showing Worthington heaters also show "Centipede" tenders, which the locomotives only received several years after they were built. And there are side-by-side photos of 5426, "as built" with an Elesco and as rebuilt with a Worthington.
---Note that both the Alco-built (600-609) and Lima-built (610-619) J2 had Coffin f.w.h. The B&A seems to have liked Coffins: their last order of Berkshires (A1c) also had Coffin heaters. (Since the B&M also had a number of Coffin-equipped locomotives, and "Coffin" is an old New England name, I wondered if this might be a "patronize local industry" thing, but the Coffin company's headquarters were in New Jersey, not New England.)
---The New York Central seems to have come to prefer Worthington f.w.h. after the construction of the last Hudsons. They are very rare on earlier power, but the L3 Mohawks were mixed (some Worthington, some Elesco) and the L4 Mohawks (and, of course, the Niagaras) all had Worthington.
---I'm guessing that the Big Four (CCC&StL) mechanical office had at least a bit of autonomy, and that their c.m.o. was early in thinking that Worthington heaters should be tried: note J1e 6620-6629 (later 5395-5404) which were built with Worthingtons. The CCC&StL also had a small number of L2 Mohawks, built in 1929, with Worthington heaters.
---
---Question: which were the two Hudsons that went to the TH&B? as I recall, they at least finished their careers with a non-standard feed water heater.