"It is better than nothing" is literally what I said. But thinking about it more, I actually think is quite useful. Any kind of signature or out-of-band hash is

"It is better than nothing" is literally what I said. But thinking about it more, I actually think is quite useful. Any kind of signature or out-of-band hash is also only good if the source is not compromised, but knowing after the fact whether you are affected or not is extremely valuable.