Fallback to object.method when necessary

Certain strangely built proxy objects can mess with out "no tampering" method lookup code, in those cases we'll try to perform the lookup the old fashioned way as a fallback, this was fixing #591 for me yesterday but for some reason I now can't replicate that, nor can I replicate it working on 2.14.2
The regression is that we're binding an original instance of method back to the object, thus restoring the original Ruby behaviour, I think that's sufficiently a bug to warrant falling back to just asking the object directly. It doesn't effect the happy path after all.