I don't understand the purpose of your example... firstly because it has nothing to do with /set, but more importantly, you created a custom function to perform something PHP does not support natively. This is exactly how we should be using mIRC in uncommon scenarios. It seems to illustrate my point better than it does yours. Yes, you can create a function that factors out duplication, this is not a surprising concept. You can do the exact same thing in mIRC:

Code:
alias add { .... }


PHP doesn't have this builtin and won't, but if you need this behaviour, you can add it and make your life easier. So why is it so wrong to share this same paradigm in mIRC? Why is it that in mIRC, the functionality must be builtin, but in PHP it seems okay to code it yourself?

The heart of this issue from my end isn't about how much easier this makes your life, it's about how common the need for such a feature is. I'm sure for that a very small number of people, this might actually be useful. The keyword being: a very small number of people.

The problem with features used by a very small number of people is that it increases maintenance strain. If -u were to ever change in /set, it would now have to be synchronized with /var. This may or may not happen properly. Worse yet, since only a small number of people actually use these alternate features, Khaled may forget about updating them in the future, and this may go un-noticed until after a release. Problems like these have happened before. He likely started to release public betas for this very reason-- but with such a small number of people making use of some functionality, a public beta might not even catch some of these issues.

You might be saying, "well it's only one more thing he has to think about, you're exaggerating the problem!" ...it's one more thing here. And one more thing there. And another thing in the other suggestions. The amount of things Khaled has to think about when making changes is probably fairly surprising. This makes it harder for him to make changes without worrying that something else will break. And all this just for a handful of people that could have written an alias to remove the duplication in their own script.

Ultimately the question is: why is it necessary for mIRC to support this builtin, but completely out of the question for the handful of scripters who want it to just make an alias for it themselves? Why is the onus always on mIRC to support all functionality?