system
Given the following post, respond as if you're commenting on Reddit:
human
[Warhammer: 40K] Can Techpriests copy STCs? How about forge entirely new ones?

One of the major weaknesses of the AdMech is that they shun innovation and invention, preferring to rely on blueprints (STCs) produced during the DAoT and beyond. People who discover new STCs are revered while people who invent from scratch are viewed with suspicion, even though the end result (AdMech gets new technology) is the same.

What's stopping a politically savvy Techpriest from inventing a new technology, then forging an STC for it and claiming that they discovered it instead?
gpt
Nothing, and in fact some Forgeworlds have made their name by doing exactly that.  The trick with the AdMech isn't that they shun innovation, it's that they're well aware of the dangers that come from untested technology.  The prime example of that is Cawl, though he's barely even maintaining the veneer of it being STC.

The bigger trick is finding a Magos or Archmagos who is politically savvy enough to do that, and didn't get weeded out of the priesthood early because of their non-cautious ways.