Ok - let's play "Who's the idiot?" - if anyone is. Let me see if I can explain this without it being too confusing!
Was driving the Jeep home from a dance class. Came around a little used, rural cloverleaf at night - pitch black. Once around onto the "new" road, there is one of those "on again, off again" lanes, so I MUST merge left. Just as I got to the end of the cloverleaf and the beginning of the rather short "on again off again" merge lane; there was what appeared to be a large truck that was coming up behind me on the "new" road - maybe a larger high-cube or something. He "twinkled" his headlites at me. By "twinkle", it appeared that the headliites and DRLs were alternating with each other, from half to full brightness - but I'm not totally sure exactly what it was as I'd never seen anything like it before. It didn't look like wig-wag.
So - WTF? I've never seen anything like this, so I didn't know what the fuck he was trying to signal to me. Headlites on full bright would have conveyed "Stay outta my way, I'm coming through."; or a brief flash or cut-out would say "Come on over into this lane". But this twinkling confused me, so I slowed WAY down in the merge lane, not that I was going fast anyway - more of a rolling stop. Then it appeared that the truck got about halfway into my lane (behind me), and twinkled his lights again. I thought briefly about FULL STOP cause I don't know what this is about or who it is, maybe even some kind of LE? But I didn't stop, and rolled on into the main lane (with signal on), he twinkled his lites at me one last time before he entered the "other half" of the cloverleaf and exited that road.
So is he an idiot for doing this? Or am I an idiot because this is something new that I don't know about? All I can say is he confused the crap out of me with an unknown signal methodology. It was absolutely pitch black, I couldn't see the square root of eff all other than this lite show. We definitely annoyed each other! Can I blame it on smartphones?