Thought on Daily #582

In daily #582 Day[9] discusses protoss vs mutalisk. He emphasizes positioning over composition. He mentions several times  that it's good to attack a particular spot because we know the mutas are on the other side of the map.

I'm wondering whether it would be worth it to get oracles for revelation. Revelation would make defense much easier, and attacking the right spot a lot easier as well. Just getting one or two oracles (2 is the number that allows for infinite revelation) would allow for constant knowledge of the mutalisk's positioning and allow you to move your forces accordingly.What are you guys' thoughts on this?