I found this: http://www.cloudforest.com/cafe/forum/12266.html
"On Knight/Pierce/etc, my understanding is that Pierce is the smooth fruit commonly called that, whereas Knight is a fruit with a number of synonyms ('rough Pierce, etc) but small bumps-- and is thus distinguishable from true or smooth Pierce. I remember at the CCA meeting a year or two ago that we were both at, I thought the Pierce was the best tasting of the 5 or so varieites they had-- the few times I've tasted it, it always had really nice lemony/acidic tones that seem great to me."
So the question is: Does Knight from LaVerne have smooth skin or small bumps?
Interesting conversation. I thought Pierce and Knight were the same thing, but the CRFG site agrees with the post you have provided. If the two varieties have difference fruit skin types and leaf sizes, then they are not true synonyms.
From the CRFG site:
Knight (syns. DV, Pierce, M&N Pierce)
Origin a Mr. Knight, Orange, Calif., 1930's. Scions imported from Mexico. Recovered from Dr. Pierce's ranch, Goleta, in 1950's and propagated under several names. Tree has medium vigor, medium-sized pale green wavy leaves. Fruit has minor protuberances, a thin skin, a slightly grainy texture and is quite sweet.
Pierce (syns. Knight, Escondido White, Ryerson, Thomson-Spain, & Bayott)
Believed to be from a group of scions imported from Mexico in the 1930's by a Mr. Knight of Orange. Dr. H. F. Pierce planted a grove in Goleta in that period made up largely of trees produced by Knight. This cultivar was Dr. Pierce's favorite and was named "Pierce" by him. Tree is vigorous with large dark green leaves. Fruit is medium sized elongated conically shaped with very smooth skin and a high sugar content.
I have a Vietnam variety of Cherimoya from LaVerne and on Cloudforest some posts suggest that this is a synonym for Knight. Not sure about this, but the fruit is rather bumpy at this stage of development.
Vietnam Cherimoya