I was planning on making another batch of weizen soon. Over on the HBD board I saw Chris White recommends 5-7m/ml for a weizen. I've never tried pitching one that low, or as high as what Narziss recommends. It sounds like an experiment is in order. It wouldn't be too hard to do a split batch and see which one turns out better.
What I've always thought was weird is that Dan Gordon has said he pitches at 6E6/mL in a hefe AND his original doctoral project was to translate Narziss into English. Why would someone who studied directly under Narziss, who still follows the Rheinhisgibot, go against tradition/teachings like that? I really think the presentation that is quoting Narziss is MISquoting him.
Also, the Eric Warner book quotes many modern German breweries pitching roughly 7E6/mL.
I brewed 2 hefes back-to-back both 1.048—one at 20E6/mL one at 6E6/mL. The idea was that since there would be less Acetyl Co-A used in cell sterol production (in the 20E6/mL) there would be more available for the production of esters (in conjunction with alcohol)—basically, I thought that under pitching was a bad idea and I wanted to prove it to myself.
I ended up proving the exact opposite. The 20E6/mL hef was initially sulfury and then just insipid—boring, some clove, nothing much as far as yeast character really. The 6E6/mL was beautiful—great balance, really nice.
I saw some slides from Neva Parker recently that showed a very wide range of pitching rates that all resulted in the same terminal gravity. Frankly, I think that homebrewers ought to play with pitching rate a bit more. Pitching rate has become a bit too dogmatic recently.