Maybe so, but they had the slight problem of getting crusades whipped their way EVERY FLIPPIN' YEAR by batshit popes.
And I don't actually own the game, I only played the demo. It taught me an important lesson about playing smaller countries (Bohemia and Scotland are your only choices in the demo) instead of larger ones, like Germany.
Germany looks very imposing, and has a ton of land to start off with. But they don't have any standing forces to back up that image, and every one of their neighbours wants a stake in that land. It didn't take long before Germany had been picked apart all the way down to two pathetic little provinces. And of course nobody would ally with Germany, because they looked too powerful to need it.
Meanwhile, Bohemia, the backwoods little hick colony of the Slavic countries, was building up its forces and munching through nearby provinces like nothing, and nobody batted an eye. After all, Bohemia? What could possibly come of them?
I also learned that, if you're completely surrounded by enemies, you should ally yourself with the guys on one side of you and fight the ones on the other side. If you do anything less-organized, you may end up spreading your forces thin or getting hemmed in by "off-limits" ally provinces.
Furthermore, "an ally is more valuable than a vassal". An ally can raise his own armies and appoint his own lords. A conquered province, however, needs to be managed by YOU, and will thus be limited by your government cap. Trying to conquer all of Europe with only eight armies can prove to be just a teensy bit tricky.
And for those of you worried about getting a dagger in the back, just remember that it's entirely possible to get an ally who adores you and wants nothing more than to help you out. Just play your politics well.