Houserule opinions, please., Crafted/built items limited by skill rating. Options

[Da9iel]

I mostly started thinking about this in regards to program maximums. Folks said that they could just have their PCs spend some downtime and create rating umpteen stealth programs and rule the matrix. But the books say that rating 7+ are uber secret miltech things. "Why is that?" I wondered. Perhaps I could say that everything with a rating needs to be made by a person with the appropriate skill equal to or greater than that rating. It's a bit of karma, but game mechanically easy to get a skill of 6, hence rating 6 programs are available. It takes, what, 48 more karma (aptitude plus double advancement costs) to get to a skill of 7? Uber enough that you could call that bleeding edge secret stuff. Adept magic can get you to a skill of 9 or even 10, but it's probably uncommon to have an adept waste his points and possibly a ton of karma in a nerd skill. Yet a rating 10 program could exist by this ruling.

Now questions for which I need feedback. (And flames. Don't forget the flames.):

How would this affect break the world?
After programs, to what items should or could I generalize it? (Focuses, nanotech, cybertech, everything but acceleration, speed, body/structure, armor, and DP?)
Is this reasonable?
Any other criticisms/feedback?

Thanks,
Da9
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