Lucky? They pounded the Bears and beat the Chiefs fair and square. I think Miami like Pittsburgh is a really good team that has just had nothing go right. That has really underperformed and needed something to turn the season around. That beatdown of the Bears might of been the thing to do it.
I agree with you that Miami's defense played well but KC could have/should have put together one offensive drive, I don't want to take anything away from Miami but KC's offense was pathetic.