Well, my question is about where it lies within the gray area between fully online and fully offline, so that wouldn't work.
Edit: Good call! It's fully offline - I disabled the network in Chrome and it worked. Says it's 176MB. I think it must be downloading part of the model, all at once, but that's just a guess.
The 176MB is in storage which makes me think that my browser will hold onto it for a while. That's quite a lot. My browser really should provide a disk clearing tool that's more like OmniDiskSweeper than Clear History. If for instance it showed just the ones over 20MB, and my profile was using 1GB, at most it would be 50, a manageable amount to go through and clear the ones I don't need.