Mark Hansen wrote:

I know that at a towered airport, you must have a clearance before
you may operate on the taxiway. I don't think anyone is trying to
dispute that. But I think the two conversations are focusing on
different aspects of the issue, which is causing some confusion.


A clearance is required to operate on a taxiway, operating on a taxiway
without a clearance does NOT constitute a runway incursion.