Your power is only as great as your connection. Thus, your ability to use the Force, your strength in the Force, is entirely dependant on the amount of midichlorians. There is effectively no difference between midichlorians and the Force itself, the point is you can use the Force because of the measureable amount of midichlorian cells. Yoda says "strong am I in the Force," but in TPM Kenobi remarks that "even Yoda doesn't have a midichlorian count [as] high [as Anakin]", which is significant in that his power is framed in terms of a measureable scientific report.
"The Force is strong in my family."
"My father has it, I have, and my sister has it too."
There has to be something measurable to support those statements.
More midichlorians, more potential the individual has, yes. But I still don't see how does it make the Force less mystical, when we are only talking about the link between a being and the Force, not the Force itself.
Wait, so is Han just a moron now that he doesn't believe in something that can be physically measured?
He said he doesn't believe in midichlorians?!