I'm suggesting that if there are no Pre lanes, then there's no point to managed inclusion, so if the doggies are there, it must be to prevent another Brussels-style attack. It is certainly much faster than swabbing and testing every single pax.

I've seen the dog once when Pre was open and the lines were long. The pooch sniffed both lines, but no one was shifted from the regular line to Pre. That's only one datapoint, of course.

I'm wondering, because I've seen TSA statements suggesting that the sniffer dogs could really speed things up at the checkpoint through 'managed inclusion', but I haven't actually seen that happen yet or read of it happening. It had no effect on the lines the day I saw the dog when Pre was actually available.