This provides more details about how to house train a Pom. This is my view, but I am always interested to hear other people's opinions.
I should point out that I am not a vet, nor do I have any related knowledge, and I can only speak from my own limited experience. If there is a medical issue involved then the vet is the person to speak to.
Firstly the structural issue: Poms do have small bladders, and don't perspire or pant as much as other dogs, so accidents are almost a fact of life, though bitches tend to cause problems rather than dogs (males). That said, you should be able to get to the position where the dog is alright for 6 hours at a time, plus overnight.Then there is the dog's personality. Poms make their entire existence revolve around their owners. They therefore pick up on a wide range of human emotions, but due to the complexity of human messages the dog is not necessarily able to clarify what is best.For example, if your dog makes a mess in the kitchen, but on a pile of newspapers laid out for the purpose, the first emotion you may have when you see the results is 'Oh no, I have to tidy that lot up again'. You may not say that, but that negative vibe may well be picked up by your Pom, who can't work out the difference between that message and a very similar message if the dog had used the front room carpet. In fact, what you need to tell yourself is 'Great, that will not take too long to sort out' and then congratulate the dog.
I don't think it is realistic to get the Pom to tell you when it is ready. It already knows you find the issue annoying, so the Pom will be defensive about it. Some Poms can do it, but in general terms they are not auto-pilot obedience animals.One important thing for the Pom is to prepare itself for the correct time period. You should have a timetable and stick to it. That way the Pom knows how long to hold out for. We take the dogs out twice first thing in the morning (6 and 7 am.), then lunchtime (see below), then 5pm when we get back from work, 8pm, 11 pm then straight to bed. We don't deviatefrom that by more than 30 minutes or so, and the Poms fall into the habit. If there is a random element to the timetable then most humans would have problems coping with that!
They are also not very good about changes to systems. I would suggest you stick to one method, forget about all the others and persevere for months if necessary. We leave about 3 broad newspapers sheets permanently down in the kitchen. If the dogs use that then it is quick and easy to clean it up, and we are grateful. In the beginning the results were not too good, but now the Poms use that 97% of the time. The other 3% generally means near misses. This is one approach, others will work too given a chance.
We took out the carpet from our kitchen and replaced it with a smart lino, which is very easy to keep clean, and costs much less than carpet so I am happy to replace it every year or two. We don't crate our dogs while we are at work, we let them run around the kitchen, and there is relatively little they can damaged there. We have put a baby gate between the kitchen and the next room, so they can't get out but at least there is the semblance of even more space for the dogs since they can see the next room. Then when we get home we just have to bin the newspapers. If they use other parts of the kitchen rather than the newspapers we would clean it up and then polish off with a strong smelling kitchen detergent. The newspaper area we clean with a gentle antiseptic spray. The dogs are sensitive to the distinction. Even if accidents have happened at least the impact is restricted.We also have someone come in at lunchtime for 20 minutes to give the dogs a quick stroll and a tidy-up. It only costs a few pounds each week, and it probably reduces the chance of a break-in. The girl who does it for us is actually a cat sitter, but she has fallen in love with our Poms. During the weekends and evenings we keep the kitchen door open, and let the Poms have the run of the house. They rarely need to use the kitchen, thanks to the timetable, and it is most unusual that they would use any other part of the appartment. The poms get a 'good dog' hug if they use the newspapers, no response if go elsewhere in the kitchen and a ticking off if they go elsewhere in the house.
Another approach is to send him to obedience classes. It will not have a direct impact on the problem, but after 10 lessons or so the Pom will have a much clearer understanding of when you are happy or upset with the dog's behaviour. You will therefore be able to communicate with your Pom as to when he has done the wrong thing. Poms are intelligent (very intelligent for their size) but they sometimes have problems working out the variations in human communications.
Incidentally, if your Pom is doing it on your bed linen, or clothing, or your favourite chair, something else is involved - he is showing his affection for you! Or rather your scent. Apart from sending the 'no-not-acceptable' message the other things you can do there is keep the bedroom out of bounds and/or double your dose of washing powder for a period of time, so the linen smells of maganese sulphate (or whatever) rather than you.