Yeah that's idiotic. I remember about 9-10 years back there was a myth going round that any cardio would throw you into a catabolic state. It didn't help that Mark Rippetoe was vocal about not doing it. Today even the power lifting guys - Dave Tate, Jim Wendler (off the top of my head) advocate middle distance runs. Lyle McDonald's done written some good stuff on this:

http://www.bodyrecomposition.com/muscle-gain/cardio-and-mass-gains.html/

http://www.bodyrecomposition.com/fat-loss/what-defines-cardio-in-terms-of-too-much-qa.html/

Extended cardio sessions can wear you out and effect your lifting, but you'd have to really over do it for them to be catabolic. With a few weeks of intensity build up you can run a solid 1-3 miles per day with no ill effects and be far fitter. Back when I used to row we'd often do 10km runs in an AM session, then a 20km row and weights session in the PM and still make solid gains.

HIIT / tempo runs are also great, but I find a certain buzz to being able to run a fast 2 miler.