I think I do agree with you MarcS, and that is one way in which Hedge Funds control stocks and also, makes tons of money, and how they operate with very low risk. They borrow shares and then short/sell them at what they see as an opportune time, per charts or patterns or whatever. They have a huge % rate of success because they can throw so much money into their shorting hit.

Thus, the massive number of shares that are presently loaned out, over 3 million, may or may not have been sold/shorted yet. and so may or may not have done their damage, by causing the sp to decline. This is getting a little complicated.
Data is that on Friday, just over 2 million shares were shorted, but over 3 million are presently loaned out/borrowed, so maybe only 1 milion shares presently borrowed, have not been shorted/sold yet and could be, or probably will be shorted/sold on Monday. Not sure about all this.
And there have been some explanations that "short interest" is different than "shares shorted". Maybe "short interest" is the total of shares borrowed, but all those borrowed shares can either been already sold/shorted or, being held, to be sold/shorted at some later time.