hi,
No I don't find this to be true, I had no problems training Willis as a pup. Although he was and is pet carrier/crate trained, Do you have a crate? Willis always went in his crate through the night in our room, and it taught him to hold his pee, it really works, although you have to make sure the crate is not too big,as they would still pee in a corner. During the day time I would leave his crate open, He was fine during the day, used puppy pads, which he always used and I slowly moved them to the back door and finally outside the back door. Give tons of praise when they pee outside, and use a word of your choice (i say wee wees) when they go, eventually the word will get them to wee on comand.
hope this helps.