I am a lake boater with a 46 Voyager. As is popular on many lakes many boaters tie up together in the bays. Usually we are not dealing with major wind gust but some days we may have some 15 to 20 mph winds pop up. It is not unusual to have multiple boats tied on either side of the anchoring vessel. I was wondering if anyone knows how much force a windless can withstand? I have this vision of seeing one being ripped from the bow.
Too many variables to give a quantitative answer. What brand windlass, how was it attached to the boat, how strong is the deck it's attached to, chain or rope, what type/size anchor. To give a short answer, generally the anchor wouldn't have enough holding power to "rip the windlass out of the deck" (although it could get hooked on something), and the brake would allow the windlass to slip before ripping it out of the deck as well.
Why not use a chain-stopper and have the deck reinforced; http://www.lewmar.com/products.asp?id=8367&type=113&channel=1
We commonly use an anchor bridle, where there is short length of rope from the chain to the port/starboard deck cleats. Zero load on the windlass. http://www.bosunsupplies.com/snubber.cfm