A good length of rope and the knowledge of how to tie a proper knot will work wonders.
Today I tried an experiment that was quite a success. I adjusted the pallet forks to their narrowest setting. The blades were only an inch or so apart. I then treated the blades like a shovel and proceeded to take out 7-8 locust trees ranging in size from 1/2 inch to 3 1/2 or 4 inches in diameter. Wow, what big roots these things have! Worked pretty good, kinda like a sharpshooter spade. I didn't have to manually handle the darned thorny things as only the pallet forks touched them.
A smaller diameter chain like 1/4 inch is better than say 3/8 or 7/16 for pulling brush (if within the strength of the chain) but I have used the larger stuff with success. The key is in knowing how to take advantage of the "CAPSTAN EFFECT." You need to know how to wrap and tie/connect the chain so that under tension it constricts and grips tighter but when you relax the tension the chain is very easy to remove.
Pat