The main problem is we're never told what the Ring's powers are; so the problem of using it safely is underspecified

According to a discussion on reddit I can't currently find the idea was that the ring inncreased the power of 'will' in Tolkeins semi-mystical sense of exerting your will upon the world.

So in lesswrong terms you have the ability to more effectively fulfill your utility function, but it will be corrupted and drift towards that of the ring.