huh ... my two blade single spring Canoe with stagalon covers made by Camillus, is just as wide/thick/fat at the bolsters and covers as my two blade two spring canoes made by Case, Buck, and Rough Ryder with smooth or jigged bone or synthetic covers.
If there is a difference, you need a micrometer (which I do not possess) to measure it.
From what I've seen over the 5 or 6 decades I've been interested in knives, the "Single Spring knives are thinner than a double spring of the same pattern!" is a myth.
I remember way back in 2018 when Buck made the forum Knife, the Spey/Budding blade was eliminated, because too many bought into the lie a 3 three spring stockman is "too thick" during the blade poll.
Guess what?!? The two spring two blade Buck 301 Forum Knife is just as "thick" as my standard production 3 spring 3 blade 301 and 371's, and takes up just as much/the same pocket Real Estate!
For some reason, my 5 inch closed single blade Coke Bottle, Daddy/Grand Daddy Barlow, and other traditional single blade knives are not any thinner than my multi blade and multi spring traditionals ...