Malarkey. That's right, I don't know what malarkey means, but you're mistaken.
I used a HP Crossfire tank all last year on my Dark without ill effects. The only gun of which I am aware that comes with a regulator that doesn't do ok on HP tanks is the Angel. Every other inline reg I ever heard of copes with HP tanks with no adjustment necessary.
No orings will be blown, no velocity will spike, and the Torpedo is super easy to maintain. Timmies were made with American players in mind, whose idea of maintainence is to spit on the bolt every couple cases and punch the gun if it doesn't shoot well.