I did that exact weizen recipe this Spring using Weyermann malt and used this mash schedule:
112F (0.75 qt/lb), hold 20 min (ferulic acid rest)
Step using boiling water to 153F, rest 60 minutes - ended up with about 2qt/lb
Decoct 1/3 of the mash (thick but with enough liquid to not scorch), 20 min
Combine (results in about 160F mash) and rest 15 minutes for any conversion (starch test)
Drain, batch sparge
Wyeast 3068 Weihenstephan Weizen, pitched about 6 million cells/mL of wort
Pitch at 56F, Ferment at 62F (30C Rule-of-Thumb)
100% RO water, CaCl2 addition only for 40ppm Ca, ferulic acid rest pH = 5.72 at room temp, added acidulated malt during step infusion for pH 5.41 room temp @ 15 min into mash.
The beer tasted amazing. Got this comment from an experienced brewer:
"I am not a huge fan of German wheat beers, but this thing blows me away. The color, fermentation, and carbonation are spot on. What sets this beer apart is the perfect banana flavor. The hops are done so well that I don't detect any bitterness, but the sweetness is balanced. I could drink this all night. I think you need to enter this this beer into competition."