I have not seen the problem you describe, but have seen something similar, as follows: This happened only in the winter time, with the heater on, and only after driving for a while so that everything is good and warm. Going down the road, high beams on. Meet a car, pull the dimmer switch and let it go, the lights went out. Hit it twice real quick and they would come back on.
This problem would not occur during the warmer months since I wasn't using the heater.
Eventually I installed a headlight harness kit from Summit Racing, which takes the headlight load off of the headlamp switch and dimmer switch. With that harness in place, the only load is that of the relays for those headlamps.
Since installing that harness, the problem with the headlights failing has disappeared. I assume it is because the headlamp and dimmer switches are now running much cooler since the load on them has been greatly reduced.
Don't know if this will be helpful to you or not, but thought I would offer what information I had that might be related or helpful.