You can't really make yarn JUST out of dog hair very well (sez my serious handspinner m-i-l), it really needs to be mixed with some percentage of wool. I don't offhand know what percentage, but she's done it for people who wanted a sweater made out of their dog's fur.
Sheep milk is certainly drinkable, miss_thenorth is drinking hers' and I've tried my Shetland ewe's milk and although there is an interesting "not from a cow" note to it it is really quite good, and very sweet and creamy-tasting.
In addition to being reasonably freezable for quality cheesemaking, the other big enticement of sheep's milk for cheese is that it produces approximately twice the yield (lbs of cheese per gallons of milk) as goat or cows milk do. So although sheep produce less milk, you also NEED less milk to make a given am't of cheese.
However, I dunno bout that article you linked to, BBH, Heather Smith Thomas is a cattle and horse person at heart and the article reads as a somewhat poorly researched book report, to me:
"Many hobby-farm families have a few sheep, and milking them could provide additional income if a local market for the milk exists"... uh, milk sales are so highly regulated in most places that you are going to have an AWFULLY difficult time SELLING it unless you go the whole-hog registered-commercial-dairy inspected-and-everything-custom-made route. It is more reasonable to say that milking one's sheep could provide additional home-produced stuff for one's own consumption.
"Sheep thrive on marginal land with minimal feed supplements, and can provide a triple income from wool, meat and milk". Sheep in GENERAL can do well on marginal land with little or no supplementation, but high-volume DAIRY sheep don't. It takes a considerable amount of high-octane alfalfa and grain to get the kind of milk yields people talk about.
"The major dairy breeds around the world are Awassi (Israel), Chios (Greece), East Friesian (Germany), Lacaune (France), Manchega (Spain) and Sarda (Italy)." What about British Milksheep, which are probably more numerous and higher-milk-producing as at least three of the abovelisted breeds. And a number of people up here (both British Milksheep AND East Friesian folks) have told me that purebred East Friesians have lower lambing success and are noticeably higher-maintenance than British Milksheep, or than East Friesian crossed out on something else.
"Due to breeding from those endeavors, East Friesian and Lacaune sheep are available in the United States and Canada." So are British Milksheep, which as far as I can tell are the main commercial dairying breed in Ontario (dunno bout the rest of Canada). I don't know whether British Milksheep are in the States at present.
You do not need a dairy-breed ram if all you want to do is milk the sheep you've got. ANYthing will freshen them ('swhy I got Jose the Shetland ram). The only reason for wanting a dairy-breed ram is if you (as I presume BBH does) want to keep the resulting ewe lambs to enlarge your milking flock.
Pat