Thanks for Proving my point.Nope. Diminishing returns are. I'm going to simply disagree with you on this.
I know of a particularly outstanding instance of one cmdr holding off an effort by the opposition that consisted of over a billion in bounties per day, at some points twice that, and once even thrice that amount. "They," were spending many manhours across multiple cmdr's to hit those amounts with nil realization that beyond a certain amount it was fruitless all the while he consistently played a highly curated set of BGS actions per tick and stopped them cold.
Time and again I've been involved with and/or seen similiar situations unfold.
Diminishing returns a not a factor, thats a constant general condition. And what factor does counter this? Time invested.
As i said, we are not looking at player groups, that have no clue of the BGS mechanic. Turning in bountys is only most effective in very special circumstances that seems to not occur in your example. The normal case is that two competent groups compete for inf. And the group that can invest more time in total will succeed.