Now as for the classification of the Enterprise as a Constittution-class starship in the Star Trek Concordance, I am accepting this on faith alone as I have never seen the first edition. Now, I would like to know, what was Bjo Trimble's source for this information?
We’ll probably never know for sure? All we know is that “Constitution” was one of the Enterprise’s sister ships listed in TMoST, and that “STAR SHIP MK IX/01 CONSTITUTION CLASS” was on the phaser schematic that Scotty was viewing in "The Trouble with Tribbles". Trimble probably just put two and two together and drew the obvious conclusion? But as to whom in the production hierarchy was responsible for Constitution-class on the schematic; it was probably Jefferies, since he was in charge of the art department.