break seen as a C archaism

[Brian Goetz]

> I think having another syntax for the block syntax of an expression switch makes little sense,
> we still have two possibilities, adding 'break value', or saying that we do not support block syntax in case of a switch expression.
> I'm still not convinced which one is the better.

Not supporting some sort of block syntax (either a block expression or a switch style block) is a non-starter.  There are too many legitimate cases excluded.