My guess is that Jim Wendler choose to add a deload week every month to give a break to the CNS and not really to the muscle..
So could the deload week be used for some high rep, low rest, non-failure workout(kind of a pump/hypertrophy training). The CNS stimulation would probably be minimal, thus still letting it recover, and that week could as a way to pump nutrient to the muscle, still stimulate the muscle and act as a mild cardio vascular training.
Exemple , after your 3 sets of the main mouvement with the % indicated for deload, 4 sets of 12-15 with around 50% 1MR ( Keeping 2-3 rep short of failure) with 60-90 sec rest beetween sets, for 2 or 3 assistance work.
What do y'all think?