My biggest objection to the idea of using detachment as a way of gaining freedom from suffering is that it's hard to see the difference between detachment and complacency, between detatchment and unambition, between detachment and lower performance. Especially when I come across explanations like this one:

"If someone gives up his occupational duties and works in Kṛṣṇa consciousness and then falls down on account of not completing his work, what loss is there on his part? And what can one gain if one performs his material activities perfectly?" Or, as the Christians say, "What profiteth a man if he gain the whole world yet suffers the loss of his eternal soul?"

But perhaps the key here is that you can be as (or perhaps more) successful at the things you do if you work at them fully engaged in the moment. The mental state that athletes are in when they're said to be in "the zone." It's not that you don't care, it's like you're too engaged to care.

I know I would have probably gotten more done at work if I didn't get worked up about things that were happening.