Yair . . .
chevy43.
hit both steering brakes and pull both clutches back with left hand to keep blade up against rock or obsticle , then lift blade to see if it breaks loose
Sort of . . . it's been so long mate, I'm doing a bit of a rehearsal here in the office chair.
When tractor bogs down, pull both steering clutches in one movement which takes drive from tracks and allows full power to be applied to hydraulics or winch . . . you may or may not need to hold tractor against obstacle with brakes.
If not already done I always modified brake pedals so I could apply both with one foot leaving the other foot free for decelerator (which not all tractors have).
If you are jammed up and can't shift obstacle or blade has slipped you then have your hydraulic or winch (right)hand free to hold steering clutches back and then disengage mater clutch as normal with left hand . . . reengage steering clutches shift into reverse and have another go.
Steering clutches should either be completely disengaged or engaged in one smooth action . . . nothing in between.
Not telling you how to suck eggs but I have seen folks try to slip them.
One thing you should be aware of on side cutting work is "sling shotting" which can occur when you pull one clutch and the other track spins and the tractor loses forward motion . . . if this happens it is always best to decelerate or preferably throw the master before allowing the steering clutch to reengage.
Cheers.