I just ran across this thread because this weekend I'll be making a dunkelweizen using 60% Dark Wheat Malt (Weyermann). For what it's worth, BeerSmith lists the diastatic power as 50 and the Midwest Supplies lists it as 76. That's enough to self-convert, and significantly more than the 10 listed on the wiki page.
I couldn't find this number listed on the Weyermann website but it does say to use up to 70% in Bavarian-style Weizenbiers while the wiki lists the max as 20%.
I'm guessing the wiki should probably be updated.