So, in the interest of a balanced perspective - I taught my class and although the trials of the dual ovens at my disposal prior to the class were not at all encouraging, the actual class went off without a hitch.
I decided to use only one of the two ovens with the broiler technique as the lower oven would have had me on my knees half the night checking to see if the broiler was on
Instead, I set up the lower oven with a double set of stones (over/under) and a max temp of 550 F. That way I had a fallback position if the broiler didn't work.
The broiler was flawless for the whole class and the pizzas looked great. The bottom oven served as a good lesson in what the same dough looked like cooked in 9 - 10 minutes vs 2 minutes and was very enlightening for my students.
So, there you go when the technique works it is not bad at all.
On a side note I found it very interesting that Mark Bittman's NYT column last week on pizza made at home did not at all reference Lahey's new book (considering the history they have together).