>big project is shown time and time again to not be effective The first week, 60 hours works. The second, it's still more productive than 40 hours, but not as

>big project is shown time and time again to not be effective The first week, 60 hours works. The second, it's still more productive than 40 hours, but not as much, after that, it isn't, then actively dips below a constant stream of 40 hour weeks. So depending on how short your spikes are, it can be fine.