Not sure what you're suggesting. A cost is a... cost. Whether it's a loss of productivity or a license cost, attributable to OPEX or CAPEX, it's still a quantifiable expenditure. If a (any) cost isn't quantifiable then I'd suggest there are bigger problems than choosing between proprietary and non-proprietary.

If the cost is attributable to the use of capacity that would otherwise be left unused (idle workers), then the marginal cost is effectively zero, even if it shows up as nonzero in the books.

dont get carried away mate - these are government employees. They typically dont work beyond 3 pm anyways - 30 minutes more to learn how to use Calc isnt killing anyone. Besides - its about long terms savings. They will save this much every year. Over time it adds up. Especially considering spain is in financial trouble right now!

The salaries for those people are real costs. If you don't add things to their to do lists, you can hire fewer people and pay less.

It's all cost.

There's usually some float in people's plans - if there isn't you tend to go the other way and have projects overrun.