I've always hunted with bows in the 65-75 pound range at my draw, which usually is at least 30 inches, and this goes back to the early 70's. BUT, last fall I was sitting in a tree with a deer directly under me, the temp was 6 degrees and it was deathly quiet. The deer had frost on it's back. I was shooting a 70 lb. longbow and when I drew it the bone pop probably trigged the 20 yard dash the deer made, and it lived for another day.
A couple weeks ago, Dick Robertson and I were discussing bow weight, and he said he had dropped down to about 53-55 pounds but used heavy arrows. He said he has never had better penetration on critters before (with arrows). I think I'll get a new bow that pulls in the high fifties at 30 inches along with some new arrows, probably in Dr. Ed's 650 grain recommended range.
As far as vegamite, I put some on toast last summer over in Oz. Of course, when you sit at the table in the morning, eating, you tend to read what's in front of you. When I got to "pond scum" on the vegamite jar, I aborted the attempt.