The hard line side is in my experience the weakest link. The alloy used for the male thread on the rubbers hose is much harder than whatever is used for the hard lines. I have never damaged the rubber hose side. I used to simply clip off the rubber hose like 1/16" above where the metallic portion began so I could put a real 14mm deep socket over that side. And then just use flare wrench on line side. But I have come to see that such additional "grip" on the 14mm side makes it too easy for me to get gorilla like with the 11mm. Even with the flare they round off at probably 70ft/lbs torque applied. It's a lowly Craftsmen model an I keep meaning to poney up for a Snap On, so it may open up under heavy load slightly. And keep in mind this is after hosing down with Brake Clean so you can get that nice thick Black undercoating off with a toothbrush, then once shiny, applying PB Blaster for at least 24hrs. 1 out 4 will always for some reason just be almost fused together. I recall Lucid doing a postmortem on one that he failed to seperate without breaking on his 940. He chalked it up to an interaction of some kind between the alloys. IDK. I ordered the MC. Here are some pics. Let's see if I can still post em.