Of course, some rods break easier than others. I have reports of 10# Helios rods wilting under heavy power, were as my 8# BII MX has taken beatings on gravel and still fishes like a trabucco. Assuming that you haven't thrown your meatwhistle into the tip section of your 6# half a dozen times, what exactly does it take to break a rod?
Also, do you have any idea what kind of pressure you're actually exerting? The most common problem I find with seasoned fly fishers is that they play it too nice.
I say seasoned because a lot of clients I take out aren't and are not afraid to manhandle their rod, and only very rarely is it too much.
If you pull you damn hardest on your rod, do you know what that translates to in pounds exerted on the tippet - not a lot.
Check this video out, listen to the amount of pounds Tim calls out and watch what it take to snap these sticks.
If you're not impressed with this factory test, here's Andy Mill (you might know him for his olympic skiing bids and Vail native) trying his best to break a Hardy 12# over a Florida shark:
How have you broken a rod?