Absolutely it could be 100% short volume and no short interest created for the day (other than for a fraction of time). We'll have to disagree on the rest. I believe there's some amount of informational value in the short volume.
It's like if you walk into a mall and you see five times as many people in the mall as usual. I would infer that sales went up for the stores. But you would also be correct in saying that it's possible that sales were zero and that all the people in the mall were all there just to return merchandise.