I looked at the material, but one thing isn't clear: is their "Kansas City" forecast talking about just the Kansas side of the metropolitan area, or both the Missouri and Kansas sides?
If it's only talking about the Kansas side, then be careful about assuming that their numbers will apply to the Missouri side. The growth on the Kansas side of the KC metro area will come from Johnson County, and has for a while. This is the southwest part of the metro area, including Overland Park, Lenexa, Olathe, and many other suburbs. There may be a small contribution from western Wyandotte County (far west Kansas City, Kansas, Bonner Springs, and a few other suburbs), but most will be coming from Johnson County.
Kansas is also having some political difficulties. The current state government passed large income tax cuts a few years ago. This worked so well that they were in danger of going in the red this spring, and had to raise sales taxes statewide. A couple of weeks ago, they had to shuffle money around between agencies again, in order to make it through the budget year. The state is also under a court order to spend more money on schools.
Several months ago, for a posting on a different site, I did some comparisons of the 2010 US Census income data for Kansas and Missouri. In Kansas, Johnson is the top county and makes 27.9% of the income in the state. Wyandotte came in fourth, at 4.01% of the income in the state. Total 2010 income statewide was about $74.0 billion dollars.
In Missouri, St. Louis County is the top county and makes 22.5% of the income in the state. Jackson County (Kansas City, Independence, Raytown, and other cities) is second and makes 11.5% of the income in the state. Total 2010 income statewide was about $148.1 billion dollars.