What Twitter Bootstrap Really Is
shout.setfive.com
shout.setfive.com
I'm curious: why not? One of the major struggles I've seen at big companies and startups alike is the "6 different shades of red" issue that LESS helps with. Another common issue is every page being designed with a different layout because each section is created in a silo -- Bootstrap helps there with the grid and standard-issue components.
In the end, I suppose this isn't all exclusive to Bootstrap (you can make your own style guides and use your own grid). But it seems to me that Bootstrap - or any CSS framework, really - gives you some common ground on which to communicate with your designers.
As you pointed out, a CSS framework would certainly help but I'd argue in that case you might be better of starting with something else.