I think this might be the first practical question on C.SE. Please don't close it because it sounds to speculative, I want to know what might be heretical about it according to Catholic doctrine.
I've been mulling over a thesis in my head concerning a wonderful metaphor I can use to explain the Holy Trinity to 7th graders.
The Holy Trinity is like a Blue Plate special served in an old timey diner. It is three portions of the same hearty meal wherein one portion precedes the second portion and the second portion precedes the third to make a complete unity in sustenance. If you removed any part of the meal it would cease to be a blue plate special.
So, is there any reason to consider this a bad metaphor (other than the fact that some prefer meat over potato and some prefer potato over peas).