Camaradie: It's funny, I just made a very similar point on another thread. Here Here! Here is the celestial navigation from my perspective. (I learned it at 16 and am now 47).
1. It is not super accurate and Frankly obsolete. It's nice to know that you are within 100 miles give or take of something I guess.
2. Ideally, you want to use a computer to make your calculations! But those pesky battries. Or you could use a pencil--no calculater and the grid.
3. It is important to chart you exact location, speed, time direction at regular intervals when sailing offshore. As so many much experienced sailors than I have noted battery failures are not only possible but likely.
The advantage of studying celestial navigation in my opinion is that it teaches you to grasp the concept of where you are in the world based upon a fixed time, (Mean Time), your speed, wind direction and current.
In my opinion, this is the problem with
GPS. It makes non-sailors think they know everything they need to know about navigation because a computer screen gives them information. Yet so many lack the most basic understanding of the principles of navigation.