the sorceror metamagic rule is definitely top 3 dumb tabletop rules
Here's another really dumb tabletop rule for you
Recent Casting Limit/Rest Interruptions
If a wizard has cast spells recently, the drain on her resources reduces her capacity to prepare new spells. When she prepares spells for the coming day, all the spells she has cast within the last 8 hours count against her daily limit.
Recent Casting Limit
As with wizards, any spells cast within the last 8 hours count against the sorcerer’s or bard’s daily limit.
So if you got into a fight at dinnertime or got woken up during your night watch and have to fight, when you finish resting and get up in the morning, even though you got 8 hours of rest, all those spells still count as cast! They're gone!
I have never seen this rule enforced across 17 yeras of PnP. Most people don't even know it exists.
Sorry for the side track but MAN there are some dumb PnP rules that we should totally ignore and that sorceror thing is one of 'em.