Well, there's a thing.
In all of our games - my Smuggler game, our Pink Mohawk style drop in LC, and our Black Trenchcoat campaign, we've been playing with stun bolt and stun ball spells not overflowing into physical. It was a thing... from when I was introduced to SR3, that that was "how it worked", which I'd just taken as the way things were. It was one of the things that made stun ball the kind of spell it was... it was "safe", it was the spell that could knock someone out, but never cause them direct harm (of course you knock someone out at the top of a building, or on a narrow bridge or whatever, and the consequences are a different matter!) - so it gave tactical utility.
I've started playing in a game with some guys in the US, and in our last session, the mage cast a big ass stunball at the bad guys, which was starting at D, and then overflowed into physical... which made me go "huh?" And of course question things. A quick read of the rulebook... no, can't find how we play this. Are we house ruling this - or just playing it "wrong"?
So in our Smuggler session tonight, I mention this, to both of the other GMs (Aswon / Jez and Marius / Lee) that ran games when I got into the hobby, and they both agreed with me... and then we checked the FAQ. Magic in the Shadows. Errata. Strange notes written on the back of a fag packet. Sideways notes in the margins of that old character sheet.
But no. Nowhere we can find has the rules we've been playing by. It seems we've all been playing with some house rule - even when we went back and checked earlier editions.
In this case, for the smuggler game we've decided that whatever spell Tads has, it's clearly NOT stunball then, but some particular special Nenet spell for knocking people out. We may look at the spell design rules to see if the drain code is that much different for a range negative health spell and work it out. But it's certainly been used both tactically and narratively as a spell that is 'safe' in that it can't physically hurt people - and I'm not happy to just suddenly retcon the fact that RAW it can.
But it just goes to show how "house rules" can creep in, or being told that's how the game works, means you accept that and build it into your head-cannon. Like the people that if asked, say C3PO was all gold, and don't remember him having a silver leg...
Any of you folks have / played with a rule that turned out not to be RAW after investigation? And did you retcon your game to fit RAW, or keep it as a house rule?