"...feel free to write a DLL."
Well, that's what I might end up doing, that or a COM object. MinGW won't compile a shared DLL with the "stdcall" calling convention, or I haven't figured out how, not that this is a MinGW forum. MSVC might do it, but an IRC client isn't hard to write from scratch, using Python and wxWidgets. Mine is about 300 lines long, though it's new and has no features. So, I'm not here because I have to be; I'm here because others might want the same thing.
"[Other applications don't.]"
No, most don't. But should mIRC continue to allow scripts, even though Firefox doesn't? Is mIRC groundbreaking enough as it is?
What is different about mIRC is that it only displays information you want temporarily, and then obscures it in favor of newer information that you sometimes want less.
Regardless, other applications do also need good scrolling. I can't change them all, or post on every forum. I use mIRC more than Word as of today, so that's where I want to start. No reason we can't use the same strategies for user interface control elements as other domains.
"I'm guessing you never complained before."
Ok, no I haven't, but in my judgement the feature isn't within reach for other applications; or they have bigger problems.
"I would simply scroll down. ...What is different about mIRC?"
No, the information isn't unacquirable; it's a matter of its quick and speedy display. You seem like a cool, reasonable fellow. Surely you ask rhetorically; surely you know how mIRC displays information. Obviously, if you could have the mouse wheel and page key scroll the perfect amount, you would.
And as for why you'd want it faster, and why you wouldn't want to waste time, you had might as well ask why I go on IRC in the first place. And surely I don't need to answer that.
I recognize that the mouse wheel and page keys are very important to you. Perhaps you worry that others scripting that behavior, is the first link in a long chain to forbidding, changing, or eliminating for you the behavior you know and need. I am not a dev of mIRC; I cannot reassure you on that count. But if you can script it, then you can stay the same, even if mIRC changes.
Besides, I'm registered.