Likely the monster saw is the 22' Titan with 2 Bluestreek 12 hp power-heads. Designed for minimizing waste in felling redwoods by cutting close to the ground. Reportedly the long chain stretched a bit on occasion.
Not much on the 22 footer but here is what Mike has to say http://www.acresinternet.com/cscc.n...8d6508f0a24f67b488256b47000ac3ea?OpenDocument
Of course, with the double-engine saw, one of the engines has to turn opposite the other. And the chain mounted "pointing" the right way. A few more potential gotchas than std. Then toss in felling monster sequoias. CYA, send me the vid, eh.