I did the JZ method on a dunkleweizen and it turned out great (WLP300, 5 gal batch, no starter). Of the concerns brought up at your homebrew meeting, my personal experience tells me to not worry about 1 & 2 (assuming you're not pitching warm yeast into cool wort, which may cause the yeast to floc out). And I suppose I might consider 3 to be a stylistic decision. I watched a Wyeast video on the NB site where the guy said the clove/banana balance can be controlled by pitch rates. Pitch low (e.g., one pack w/o a starter) to emphasize banana, pitch high (e.g., 2L starter) to emphasize clove. I haven't played with pitch rate on a hefe enough to comment on this, just thought I'd pass it along since everything else I read suggests the balance is controlled by ferm temp rather than pitch rate. I do know that Dan Gordon, or Gordon Biersch, pitches about 3 million/ml, which is close to one pack into a 5 gal batch, and his hefe is fantastic. Interested to see what more experienced brewers have to say.