Joule,
It is not actually the rest period which initiates the spikes, but a cool temperature fluctuation in early fall which triggers spike production. In most spring blooming hybrids, you will see flower spikes showing from the base of the mature growths in early September in our Nor Cal area. I personally think there are other factors which contribute to spike initiation in late summer, but a rest period is definitely not one of them.
But I always say, if you are having success with what you are doing, keep doing it, even though it may not be what will work best for others.
CL