aboonski,
I don't know where all they could be used on a deuce yet, because I still have to pick mine up, but I can tell you this much. We use them all the time at work and they are soooooo much nicer than a zerk fitting. If you find a place to use them, get the proper coupler and put one on a grease gun and use them!!! They are easy to keep clean, just wipe across them with a rag, and presto...clean. The coupler has an o-ring inside of it so you get a tremendous seal, and if you have a flexable hose on your gun, you can swivel 360 like I said. No need to worry about the zerk being on perfectly straight and having grease ooze out the sides because it can't. With the o-ring and design of the coupler, plugged lines are not a problem with a high pressure gun, you can blow right through the clog. Those kind of fittings are the cats meow. If they hold up to the hellish environment of a steel mill, they'll work great on an MV!
Here are some pictures of the fittings and couplers. The manufacturer we use at work is Alemite, but I'm sure other companies make the couplers. I doctored up the one picture to show you kind of how they fit together and you can see the sealing ring inside. The first coupler picture is the kind we use at work, rated for 10,000 lbs.