It's correct as written. See sense 9 at http://dictionary.reference.com/browse/shear -- shearing stress is the stress between two blocks pressed together along a plane and moving in opposite directions parallel to that plane.

It's a very nice analogy: the startup is moving fast in one direction and the VC or whatever is moving slowly in another one.

pg actually spelt it out during the talk, as well.

What do you mean by "block quotes"?

  You can already use "Code Mode"
  to quote exactly, get things in
  a different font, and formatted
  exactly as you wish.

It's a fixed width font, though.

The pattern of block quotes tends to degrade comment quality