Mine understands that if there is a pee pad in the room, he can use it...however he will go if there isn't one there. I am trying to teach him that when we are home, he has to ask me to go. I also think that having something different...like a pad in a litter box, or litter box training, or what I got (pup head) is a sure indication that "this" is the place to go and it is different from everything else in the house. I got mine to go on pee pads (and am now trying this pup head dog toilet thing) by putting him in a small space (like the bathroom), saying "go pee", and waiting forever until he did it and praise praise praise. Now he does not have an accident if a pee pad is there but like I said, I need him to ask because I don't want pee pads all over my house and travel a lot with him.
If he was having accidents at night in my room...I would either put a belly band on him at night or crate him at night. I have no problem crating dogs at night because they are sleeping anyways. Even when I travel, I am teaching him to stay in his bag for longer BUT I am with him the whole time and he gets plenty of outside time...lots and lots actually.
I'm not for crating a dog while I am gone for hours and hours.
This article explains why I dont' like crate training for long periods of time BUT I think that crate training can be used in other ways which benefits people and doesn't hurt the dog.
http://warreneckstein.com/pettips_caging.html
suz