Agile PM would actually put process first and simply measure output because poor processes impact everything else and give you no chance of sustained success. You should be trying to optimise the conditions for optimal outcomes via facilitation. That's the reason you measure, to understand and improve your success as a facilitator for the whole team, not to track individual productivity. You shouldn't reward or penalise anybody on outcomes themselves but on ability and diligence (which should be blindingly obvious to a technical manager given any degree of engagement with the development process).