Turn wrap column to 80 (or 40). Make sure you disable word wrap, then click Show Wrap Column.
All is well when you're typing-- the line does not wrap, though you see the wrap column. However, comment a line automatically (command /) and the line will be soft-wrapped. Uncommenting the line using command / will then revert to not wrapping.
I'm writing python, so I'm not sure if it's a bundle issue, but it seemed odd to me. Not a big deal by any means.