That was my thinking, they use the toothless ring as a brake to slow the gears at the shift but no synchronizing.
Those were sold by Mr.Gasket back in the day and you are correct they were used top slow down the gear for easier shifting when the gears were "slicked-up". I used to have a set for a Muncie in a bubble pack distributed by Speed Industries from Medina Ohio but made by Mr.Gasket.
Don't know why they put them in the transmission you are working on. That thing must have shifted like crap at any speed.
Gus
