John B wrote:

The poor design element is that you can't validate on a bus, thereby
making validation actually an issue instead of the non-issue it ought
to be (yes, I know the excuses for this; however, it'd be trivially
easy to make bus-based readers connect to the base by GPRS every five
minutes to exchange relevant data with the central system).

I think we have different definitions of "trivial."
--
Michael Hoffman