HD1 required?

[Jim Hall]

I was wondering..are FM stations broadcasting in HD *required* to run an HD1
service that duplicates the analog programming? For example, WEEI-FM, WTKK,
and WBZ-FM all run "spoken word" formats on their analog signals which are
not improved in clarity that greatly in HD. So, could WTKK, for example, run
its talk programming only on analog, skip HD1 duplicating the analog, keep
HD2 as Irish music, and then run additional HD sub-channels with additional
programming? Not running the HD1 would give them more bandwidth for a
high-clarity HD3 if they wanted to run another music program there. Often
HD3's are used for spoken word because there is not as much bandwidth
available.