what is it with MIL's wanting their grandchildren to be potty-trained
At the church nursery, i've occasionally gotten comments from grandma's "i think he's ready, but my daughter doesn't" types of comments.
As far as the methods she's suggesting, i think part of it is that it's not a natural consequence to with-hold those things. they aren't even related to the potty training. IMHO, it's a punishment
so if you don't use that type of punishment in every day life then it wouldn't be the way to go for you or ds. I think that something along the lines of "if they have an accident have them learn to clean it up/change and do practice runs to try to make it in time" is a lot more of a natural/logical type of approach. HTH!