I opened up a box with two switches to witness this:
The hot (which is white, I've confirmed) is looped around the far light switch, then pushed into the connector in the back of the near light switch. Each of the red and black wires (neutrals I think) then complete the circuit, so I guess it works.
Is this an undesirable configuration? I'm trying to replace them with simple dimmer switches, and what I would like to do is pigtail the single hot with the hots of each dimmer switch. Each switch would still have it own neutral. Is this a better way to go than the current setup?