Geez. A lot of concern about minimum insertion. Isn't that a CPSC thing? Didn't we survive without it, for 100 years? Don't we still make lawyer lips jokes?
Cut it. I have bought many cut stems. Usually Ambrosio because they didn't drill a stress reliever at the ends of their slots. They crack, previous owners extend the slots, trim the excess. It just is, get over it.
Maybe.
But I happen to know that you had a catastrophic crash while riding a bike that had a cut-down stem. It also had filed-off lawyer lips, removed turkey levers, and a tiny spot of rust on the downtube that had eaten away the steel to a thin bit of foil.
And all failed at the exact same time, while you were on a steep Alpine descent.
You skidded across the road in a cloud of dust, launched over the guardrail and into the sky, only barely coming to rest in the top of a spindly pine tree, which you held onto for dear life.
Then the top of the tree began to bend, coming to a 90 degree angle, and dangling you over a yawning abyss, at which point you held out a little sign reading 'HELP.'
Then the tree snapped, and you plummeted downward, hundreds of feet.
You landed in a heap and were just picking your bruised self up when an ominous sound caused you to look up.
Your eyes diminished to pinpricks.
It was an anvil.
So, you know, maybe you're not the best person to talk about safety.