starting at

Accepting my initial misinterpretation of what was not a bug, I might suggest alternative phrasing ... not that you're asking, but it does seem at least possible to discuss. :-)

What about replacing "starting at" with "bound by"? Not sure if the majority would accept it but it seems to describe the behavior more clearly to me.

Alternatively, the whole thing could be boiled down to Search From -or- To  /n  Present -or- YMD (with the GUI elements in the appropriate spots). Still not sure that's any better than what's already there, if I must be completely honest, but it is reasonably simple.

The completely general case of specifying two dates (From and To) would of course add to the complexity of an already complicated form. I assume that this would be undesired and unacceptable.

Minimal URL

I like this minimal URL thing. By coincidence, I use the same logic for the search forms I made at work. Started as just a debug for myself and ended up being a popular little feature. Thanks for the historical explanation for nf=0.

inconsistent results

Tried to reproduce what I think I saw as different behavior from nf=1 but haven't been able to do so. At this point, I'll have to mark it up to my own delusion. I shouldn't have used that phrase without a solid example (whether it was true or not).