Maybe it depends on how you define the two terms, but I disagree, or at least what you’re saying wasn’t my intent. I think understanding emotions is the primary way to deal with them, but I added the bit about channeling it because sometimes understanding isn’t enough and something more needs to be done. In my mind controlling an emotion means exerting willpower to push down or replace an emotion that arises, while channeling entails a greater degree of acceptance of the emotion and then purposefully putting it toward something productive.

In the context of this scenario, demanding acceptance when the present emotion is probably some mix of disgust, confusion, and fear summed up as “I don’t like it” is a form of emotional control that isn’t healthy. After understanding what emotions are in the mix and (hopefully) why those emotions are present, there are productive and healthy ways to deal with them without trying to force them to change. Confusion has the most obvious way to “channel” it by researching polyamory to be less confused. You may say that that’s not really channeling, and I agree that it can be a vague term, but without that confusion (or by rejecting it) I doubt there would be curiosity to learn, which would hamper a healthy response. I feel pretty deep in the weeds at this point, but I hope that clarifies what I’m trying to say a little.

Basically, to use definitions from Merriam-Webster, to control is to “to exercise restraining or directing influence over” emotions, while to channel is to “to convey or direct [emotions] into or through a channel” toward something productive. The first isn’t a healthy coping mechanism in the long run, the second is if done right.