Management ahold be making those decisions based on ROI. That implies they are responsible for understanding the value the change will bring and you are respons

Management ahold be making those decisions based on ROI. That implies they are responsible for understanding the value the change will bring and you are responsible for educating on the costs. I would respond to the "It's impossible?" question with "Is it worth seven man days of work, a potential for tricky-to-find bugs because we adding a square peg to a round whole which will increase maintenance costs, and the opportunities lost by me not working on something else for those seven man days?" I've worked at few places that have done the real analysis to know the answer to that, but very few even consider it.