Lightswitchesoffatnight, I find it incredibly worring, and almost unbelievable, that you will not read exactly what medievalist (sorry, if I have not got your name quite right medi) is saying. If you were coming across as illiterate I could maybe understand it more, but you are not.
Cages are ok for sleeping in, PROVIDED:
The door is left OPEN,
There is ROOM for the dog to stand up completely, and to be able to turn around and lie at whatever angle is most comfortable FOR the dog,
There is plenty of thick, comfortable bedding FOR the dog to be comfortable,
That the dog has one or two of it's favourite toys nearby, and water available to it at ALL times,
That the cage is NOT in a draft,
That there is at least a nightlight (electric) ON in the room the dog is in at night - therefore, NOT having the Light Switches Off at Night, and that the light does not shine directly into the cage from any angle, and is not bright.
That the room the dog is in, is ALWAYS at a comfortable temperature FOR the Dog (of course all of these points, apart from the first one, are completely necessary wherever the dog has it's bed).
That the Cage is NEVER used FOR training the dog not to poo or pee inside. This is for at least 2 reasons;
a).. Dogs do not like to soil their beds - a fact most of us seem to agree on here.
So to blackmail them to not RELIEVE themselves as it is AGAINST their nature to hold in their pees and poos, means that you are making that dog VERY uncomfortable, which is totally FOR YOUR SAKE, not the dogs. This could actually cause damage to the dogs' kidneys if it were not for the fact that the dog would end up having to relieve itself, on it's bed, if the dog's guardian forgets, is too busy, has to go out suddenly etc, to take their dog outside every ½ - 1 hour during it's daytime training. There is then one very unhappy dog, that has to sit in it's own urine and or faeces, until it's "guardian" turns up". Added to the fact that far too many "guardians" will actually have the nerve to be cross with the dog, may punish it, and any progress teaching a dog to relieve itself outside may well have just been lost too. A dog needs consistency in all aspects of it's life, but particularly where any sort of training is being attempted.
b) FOR the dog to be "toilet trained" which this method can't do kindly anyway, the cage door HAS to be SHUT and LOCKED (remember at the start of this, a cage is only ok if it's door is left OPEN) All of which will be in the day for most people, as they will be asleep at night - now Lightsoffatnight, you may be one of the few people who will actually get out of bed hourly whilst the dog is downstairs locked in it's cage, and going through it's toilet training, or maybe you even sleep on a settee whilst the toilet training is ongoing, but please believe me, MOST people will not.
I don't know where you got your mistaken belief that dog's like or even love their LOCKED cages, except that is an untruth bandied about by people who have either ulteriour motives to do so, or by those who haven't got enough logical commonsense to realise that no sentient being would enjoy being locked in a cage. I think that you hinted that we shouldn't anthromorphise our dogs (and presumably other animals), but are you sure about that? I read a transcript of a talk given by a lady called Laurel Braitman, it was a talk through an organisation called TED, here is a little extract of her talk:
"So one thing that I would really like people to feel is that you really should feel empowered to make some assumptions about the creatures that you know well. So when it comes to your dog or your cat or maybe your one-armed monkey that you happen to know, if you think that they are traumatized or depressed, you're probably right. This is extremely anthropomorphic, or the assignation of human characteristics onto non-human animals or things. I don't think, though, that that's a problem. I don't think that we can not anthropomorphize. It's not as if you can take your human brain out of your head and put it in a jar and then use it to think about another animal thinking. We will always be one animal wondering about the emotional experience of another animal".
One last thing Lightswitchesoffatnight, you appear to claim that you know LOTS of people who put their dogs in cages and that they all know how to do that it humanely, ie keep the doors OPEN - do you honestly know all these people personally, and know that they are telling the truth, because that is the complete opposite of what I have found when reading articles about caging dogs, and forams where people have, like here today, discussed/argued about the rights and wrongs of caging dogs, and very sadly, many of the posters have no idea that to cage a dog kindly, the cage door has to be left open, and the dogs need to have reasonable choices available to them to where they want to be.
You, yourself say how much easier toilet traing your dog was by caging it throughout that period, but that was ONLY easier FOR you, not your poor dog. You had to have your dog's cage closed and locked, otherwise that "method" of making it try to hold on to it's urine and faeces (as it wouldn't want to "go" on it's bed) couldn't work, as it would just leave it's cage, and do it's toilet somewhere else in the room.