In my opinion, this is one of THE silliest and moronic things that anyone can ever say.
First off, if as the dominant, your personality and dominance are so fragile that they can be manipulated and overpowered by the submissive, then I think that dominant needs to be the one kneeling and wear the collar.
Dominance comes from many places. But one of the key aspects of it is self-confidence and the ability to project that. There are very strong submissives out there who will just run all over a weak dominant. And those dominants have no business trying to exert any sort of power or control over a submissive of that type.
It's been a pet peeve of mine for a very long time to hear so-called dominants who fall apart when the submissive suggests something, or asks for some particluar type of play.. "you ruined the scene for me! wah!"....
If you, as a dominant, are so weak as to feel broken or threatened by a submissive, then you really should not claim the mantle of dominance. As the dominant, it is your responsibility alone to project the proper power and control over your submissive. If you can't do that... then you are wasting your time and theirs.
In reality there is no such thing as topping from the bottom. That just can't happen to real dominants. Requests, demands, begging, etc, for something specific by the submissive should be easily ignored if you are truly dominant. Any dominant who is influenced, let along manipulated or controlled by the bottom clearly is not.