dak723, unfortunately I think your assessment is incorrect. The higher the MP count for the same sensor size the more likely you are to encounter blur. This is because there are more pixels per unit area with a higher MP sensor and therefore the resolving power is higher. Blur is caused by an image moving across multiple pixels during he course of the exposure.
Using the mkiii and mkiv sensors as an example. Lets say you're photographing a racing car as it moves from left to right across your frame.
Lets say that on the mkiii with its 5760 horizontal pixels, during the exposure the car moves across 100 pixels giving 100 pixels of blur. On the mkiv which has 6720 it would move across nearly 117 pixels . . . giving 17 pixels more of blur.
This is one of the reasons why the top end cameras, like the Canon 1Dx mkII and the Nikon D5, which are aimed at sports shooters are not so geared towards the megapixel race. It makes it harder to freeze the action with the increase in pixel count.