Some butchers used to sell chicken as "soft," "medium," or "hard," referring to their tenderness, which is usually a function of age. Older hens and roosters -- egg-layers no longer laying eggs, and roosters no longer fertilizing them -- have tough meat. Now, a general rule of thumb where meat is concerned is that the more a muscle is used, the tougher the meat will be, but the more flavor it will have; if you can braise it to get at that flavor, you're in business. This is why beef cheeks are so flavorful: that's the cud-chewing cow's most-used muscle.
As a point of comparison: we raised chickens when I was a kid. Chickens of the age we're talking about are going to be about two years old, chickens that had time enough to see all the best parts of Arrested Development. Maybe a little younger, not much. That Perdue chicken in the supermarket? Maybe two months old if that, never saw the seasons change. Chicken used to have flavor. Even the white meat. The last fifty years have nurtured it out.
Another google hit says that some chickens are bred to be hard -- to keep a firm texture after cooking, making them suitable for soup. I suppose that's possible too.
Whether this chicken was bred hard or just aged its way into it, this is what I learned by cutting it up: the joints are unusually tenacious. I have a Wusthof knife, and while it does need a professional sharpening, it's still sharper than most home knives and never gives me trouble with chicken. But not only were these joints trickier to get through, the chicken didn't want to move around much -- one of the thighs was resistant enough that as it twisted in my hand, I wound up slipping the skin off by mistake in the process of severing the joint.
Furthermore, the drumsticks are disproportionately large -- relative not only to the chicken as a whole, but to the thigh. This is a long-legged bird.
What do you do with old chickens? Usually you make soup. There's also coq au vin -- "rooster with wine" -- which takes advantage of the toughness of a rooster to put it through a process that a young spring chicken wouldn't tolerate, marinating it in wine for days before braising it. You can do the same thing to make adobo. I find there is not much good in a rooster's breast, so that's best for stock ... but I don't know if that's going to be true for this bird or not.
I'm thinking I'll freeze half the chicken, for coq au vin at a later date, and make adobo with the other half.
Here's the kicker: I don't have any soy sauce (except for that Bluegrass soy sauce, and I need more than that for adobo). Battambang Market has some odd elisions -- not much of a candy selection (notice there's no Pocky, no weird Mentos, no gummi candies in the photo spread), and I swear to you, as much as you think every Asian market has a soy sauce aisle ... I've never found it at Battambang. Granted, things are sometimes organized along a logic I don't follow, with oyster sauce in two different places (different brands - different national origins?), but ... I'm just saying, I couldn't find any soy sauce yesterday.