Honestly I was scared to make this change, for the longest time I thought my emotional investment was what made me a good developer, "I actually cared". While that might have helped the companies I worked for, it did not help me nor my general wellbeing. I'm much more laid back and I'm quick to say "I'll implement it however you decide" and not really care about the outcome. I'll aways warn about side effects or how a decision might affect us down the road but I don't get angry anymore.
If you find yourself getting angry at work about decisions or you get into heated discussions how to implement things (like I did) I recommend you consider taking a step back and realizing that it doesn't really matter and it's not worth getting worked up about.
Now I can’t even imagine summoning up that kind of energy over a work thing. I used to think “old guys” were lazy and apathetic… and well, here I am ;P