An ambitious plan is emerging in Congress that, if approved, would represent the most sweeping overhaul of the way agencies buy and manage information technology since the 1996 Clinger-Cohen Act, which created chief information officers at all agencies.At its center is a redefinition of what is a federal CIO: The proposal by House Government Oversight Committee Chairman Darrell Issa, R-Calif., would reduce the number of CIOs in government — to one per agency — and empower those remaining with more authority to decide how their departments’ IT dollars are spent.“The Clinger[-Cohen] Act … needs an overhaul for one most important reason, and that