Arthur,
Thank you for your question and suggestion.
The included Lionel 2 button controller has 4 small spade connectors which connect to the underside of the Operating track section and provide power to the auxiliary (Operating/Unloading) rails or its electro-magnetic coil (Decouple). The side contacts however seem to be designed to make connections with accessories that would snap in place of the removable roadbed sides, making compression electrical connections with these hypothetical accessories' mating contacts.
You may be onto something with your question about the controller. As electricity often flows in more than one direction, these contacts might also provide the ability for a side attached accessory to control some of the Operating Track's functionality.
But at this point it's just speculation...
