I tried the ANA/LH Priority lane and the UA Priority lane in T1, this is my home airport. Both are using WBIs and I don't see any rhyme or reason to the timing, it happens throughout the day, but it seems like the mornings are the worst. Agree that ANA/LH checkpoint seems to be WBI almost 100% of the time.

I opt-out every time and the molestations are usually completed rather quickly and relatively painlessly, as far as molestations go (compared to other airports).

I think T2 would probably be a safer bet (when I used to fly through there WBIs were rarely used), but its still not that convenient. Just opt-out.