Hold on there pardner!
Your instinct to err on the side of caution is correct of course, however the value in rapid testing (and by that I mean the PCR HIV test that can detect exposure in just a matter of weeks) is that you can identify someone almost before they become infectious. Yes, I did say 'almost', so I'm acknowledging that there's still risk here.
However the central point is still: someone who tests negative is less likely to be positive than the random unknown girl out there. Sounds kinda obvious when you say it out loud like that.
Your point is that you might be testing them a week before they would register on a test, but that also means that they are less infective, if they're infective at all. This is why 6 week testing for porn stars is the norm and why it works well in that industry (I think it's every 6 weeks, any porn stars here able to confirm?

).
If something as important as an HIV test returned false NEGATIVES then such a test would never get approved. If anything they skew the sensitivity so that you get 0 false negatives and a few false positives (that must scare the bejeezus out of some folks!

).
Anyway, I don't mean to argue the merits of going BB on the results of the oral test. I was just wondering what the experience with the test has been around here.