Oh, it gets better, because I didn't mention how blocks are called.

Method: m1(10)
Proc: m1.call(10)
Block: yield 10

Methods/procs/blocks are just a variation on a theme. Any sane designer would merge all three into the single entity they rightfully should be. The different behaviours (and performance characteristics!) of each of these indicates a fundamental misunderstanding of objects and closures.

Which leads me to conclude that Matz is good at cherry-picking ideas from other languages, but not at synthesizing them. This whole subject is, like, really old news in the PL world.