If I understand correctly, this sort of behavior for the program would be perceived as against the rules. I'd like to argue that it's not against them; rather, they are silent on the matter. That is, it's not specified one way or the other what a client program should do in this case. Therefore, it's not so much against the rules, as outside them.

I don't know mIRC well enough to know if there are any features it supports that aren't official IRC behaviors. Are there? If so, what? If not, why not?

Furthermore, regardless of the letter of the official IRC spec., I think the proposed modification is consistent with the spirit of it. Script-making already interferes with the "raw text" of IRC, and presumably most (or all) of what my MITM program does mIRC could do in scripts.

I think the basic image I'd like to portray is "client chaining", which may not necessarily be precedented. Clients needn't demand to be connected directly to the source network. Instead, they could permit chains as the user sees fit. It may be a matter of permitting them or denying them as a class entirely, to recognize messages that are from the user's nick.

Is this a matter for the Feature Suggestions forum?

Thanks and sincerely.