Lactose a Problem, but Milk is Not?

"Leichter (12) has concluded that on the average, the intensity of symptoms in lactose intolerant individuals was highest with an aqueous lactose solution, lower with skim milk, and lowest with whole milk."

This study also finds that the Masai, who subsist in large amount on milk, with no ill effects, are largely lactose intolerant (62%). 

"Despite this, the Masai drink large quantities of milk each day without symptoms [of lactose intolerance]."

So clearly it's not the lactose in milk that is the problem with those who are "lactose intolerant".  I'll note searching for the word "pasteur", as in Pasteurization, returns nothing in the linked PDF.  I highly doubt the Masai drink pasteurized milk.

Lactose malabsorption among Masai children

I also read and hear regularly in the Paleo community that diary is a no-no because only Europeans are evolved to digest it.  It turns out that tolerance for lactose is widespread in Africa, which puts the lie to the claim that the inclusion of dairy in the human diet is a recent phenomenon.