A lot of smart things have been said on this thread... In thinking about it I just wanted to spell out a couple of things that are never actually said by anyone though. I don't know the reason they aren't said...
first, there was a reason the sabbath was instituted. Taking time to have hands off, not do anything related to whatever goal even including planning for it, can be a very beneficial thing. The original take on the day was not to do anything not even move about very much... and I can sorta see advantages even to that although I don't do it.
second, to achieve a goal sometimes you have to go in the opposite direction to the one it seems 'sensible' to go in. It is in some way like rubber bands, if they are tangled and you keep pulling on them it doesn't help; they remain tangled and you can't do much about it because of all the tension. So you quit pulling and then there is room to unweave one from the other... Or it is like being at a high peak and wanting to climb to the next higher one... you can't directly go up because you haven't yet learned to fly, so what you do is go down into the valley and look for the path to the higher peak.
by the way that phrase you hate so much can be useful in certain circumstances. It doesn't *have* to mean to give up