I'd never seen a JVH pawl on a lever like that before. The click switch was attached directly to the pawl ...so I'm not sure what the lever was for. Perhaps some theoretical form of stabilization of movement in and out of the spring ?
What I do know is the click switch (even after oiling) was very stiff. Maybe that's why the lever wasn't used on later reels.
Dean...I think you probably nailed that hypothesis. I'd bet it was for stabilzation and an attempt to mitigate any hard rubber wear, as the button was pushed back and forth over time. It also makes sence that the brass pawl tightens the throw. Thats a lot of extra meat there. Nice little reel for sure.
Augustus Hendrick/Star Reel Works used a similar click. Don't know whose was first but probably JVH's. As Steve Vernon said, there is a lot of copying going on!