Originators of alternative mortgage products are securitizing a good chunk of their production through programs designed for prime jumbo mortgages. But a new analysis by Inside Alternative Mortgages suggests that the so-called prime mix market slowed a bit late in the year. Some $91.91 billion in prime mix MBS – or pools that contain at least 45 percent conforming balance loans – were securitized in the non-agency MBS market. Most of that production came… [One data table included]