The complaint and approach is a very recurring theme in IT, whether it's budget ($) or any other resource. In working with data center managers and IT professionals on energy efficiency, the metrics which have failed us is looking and addressing just the incrementals. The example provided calls out for an opportunity-cost analysis, a what-if impact analysis in terms of the business. An example I use for redundancy and energy efficiency, is the 1hr downtime and 3hour re-establish bsn operations (small bsn) vs. the ongoing energy, equipment, and maintenance costs.
That level of opportunity cost usually begin to wake up the CxO's.