I don’t use disposable piping bags but I don’t think it would make a difference, my experience is in how much is in the bag, i have also found at work that I need to scrape out the residual icing that is left in the upper part of the bags from the other decorators so there isn’t much of a build up or bulkiness where i twist the bag, and like you mentioned the temperature/pliability of the fondant is helpful as well, same goes for the icings at work, we have some that are quite firm ( especially during the winter months when the pails are left sitting beside an outside wall) and i need to put them back in the mixer to soften them so I am able to work with them more easily.
