mahjong rulesets are wild. I play Japanese mahjong, and the difference between online and a mahjong parlor is quite different, making it interesting to see what people optimize for in those different settings

I think mahjong is probably "house rules the game" though. Pretty sure most mahjong hands probably just were a result of some guy being like "hey this hand looks like it should be scored man".

It's similar to dominos then - every region and cultural/ethnic group has their own variant, and every family has their own house rules. Or craps! I was so confused my first time playing in a casino after learning to play in the streets.

In my city, Guangdong, Cantonese mahjong doesn't allow chows, only pongs, and you need to self-draw to win.

Yeah, the grad students near me always play Sichuan-style, because it's simpler (only numbered tiles, scoring is a bit easier).