I answered a similar question about the capabilities of Rule Bending a while back, and I think it would work here too:
"Rule Bending can be considered in a similar manner to Probability Manipulation, in that it can't make things that genuinely can't happen do so, but it can bend the rules in its favour.
For example, it can't make something out of nothing, because that violates the conservation of energy, but it can bend the rules governing the movement of particles to make them come together into a particular structure. Such a thing isn't technically impossible, it's just so unlikely as to be virtually impossible, and by bending the rules, Rule Bending can make it a significant possibility
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So in a sense, depending on the extent (how much it can bend the rules) and domain (what I'm calling the range of rules it can bend - e.g the laws of Physics, Metaphysics, etc) of the Rule Bending, it can do anything so long as it is technically possible within the rules set. It can never do something which is completely impossible within the rules, but things which are simply so unlikely as to be considered effectively impossible are fair game.
Again though, it really depends on the extent of the rule bending, and what laws it can actually bend."
This would also extend to doing difficult things with ease. So long as it is technically possible to be done and the rules surrounding it are within the user's domain, they could bend the rules surrounding the thing they are trying to do and make an incredibly difficult task easy for themselves.
Generally, the effects revert after a time, so self/body supremecy would be undone once the rule bending stops. Arguably, you could bend the rules behind development to allow yourself to develop much faster, gaining a permanent increase since the end result isn't because of the rule bending, it was just made easier to reach by it.