If I Borrow Shares To Provide Them To Another Entity, I Borrow Them At a Set Price Level (i.e. ASR)
So, my borrowing share price level is the most I should want to pay (the maximum price level) to buy back shares to break even on the deal, even if I am just taking a small percentage service fee for providing a set dollar amount of shares to an ASR plan for $5 billion.
Now, if I don't short the stock to lower my purchase price, the price of the stock can get seriously "out of hand", and eat up my service fee very quickly, not even counting the loss I could take by purchasing shares above my borrowing price. JMHO.