Splitting the Check

Splitsville
Photo: abovethelaw.com
I agree with SLOG’s Bethany Jean Clement and the person she quotes from the Awl, a website with the tagline "Be less stupid."
It seems to me that, except in the most egregious of circumstances (you had coffee, they had the tasting menu), checks should be split.
The thing that happens in groups sometimes, when people all put their initials next to the stuff they order and then hand the server a bunch of Bank of America cards like "figure it out, cool?" That is the worst thing. And unlike the writer at the Awl, I don’t care if you’re under 25. You should still not do that.
Also, when I was growing up I was taught you paid 15 percent unless service was exceptional, but now I tip 20 unless the service is brutal. And even if the service is brutal I usually tip about 20 percent because it seems passive aggressive to express my unspoken complaints by undertipping. But did the standard percentage change from 15 to 20 at some point in history, or did I just come from a very miserly town?