The Zeigler report at
http://sw-eng.falls-church.va.us/AdaIC/docs/reports/cada/cada_art.html
looks like good data.  Why was it not 'adequate'?  Was conflicting data
presented?  Is it analogous to smoking and lung cancer in that some folks
will never consider it adequate in their lifetimes?
  Or perhaps 'cheaper and less buggy' isn't really important?  Is part
of the argument for COTS that 1/N of the cost of a system that's very
expensive is still less than 1/n of a cheaper system if N >> n?  What
about the cost to each customer (as opposed to the cost to the vendor)
of more bugs?  Are we Ada-philes simply mistaken in our implicit
belief that quality is cost-effective?