This sounds like a new technique ... to me.
Could you please explain?
or perhaps provide a link so I (and perhaps others) can learn more about it?
Not knowing what you are doing, I really can't answer your question about whether to return or not.
However, usually our gut reactions are telling us the truth ... if we listen!
So, if you think they are not the right size ... I'd say return and get what you think is correct.