The answer is that putting a device on a smart plug, may or may not eventually help with a native detection, but you shouldn’t count on that. Here’s why - most of the devices that you are likely to put on smart plugs are DC electronics. Those almost always don’t conform to the main Sense native detection model, that looks for quick and clear on and off transitions. And even putting a device that does use the type of transitions that Sense looks for, it’s not a direct learning process - Sense collects the data over the long haul, and eventually enhances their general models based on the data. They don’t learn the specific device in your house.
Given that, my approach to smart plugs is to use them on most of my electronics.