I think developers themselves should know best if/which hacks are necessary, if at all. They should understand what exactly code does, its pros and cons, if it can break something(else) or not and if its worth of its benefit overall. I personally think they should try to avoid any hacks in general whenever possible until really necessary.
E7400 @ 3.6Ghz 1.33v, GTX-260 192SP 650/1400/1100/1.05v, 4Gb RAM, Windows Server 2008 x86