I think you are correct. I added a link to an interesting read that goes over accuracy and velocity.
Oops accidentally deleted the comment you're referring to. Any real disadvantages to a 20 inch barrel, like on the Vanguard carbine? Would the lost velocity make a practical difference? The standard length barrel on the Vanguard is 24 inches and it's 22 on the Howa, and I also think the barrel is thinner on the carbine.