Changed IComparableWrapper.Compare to remove some unnecessary dynamic casts.  Seems to slightly improve performance with sorting. There are some more places that IComparable checks can be cached, but they don't seem to improve performance at all.
Changed IComparableWrapper.Compare to remove some unnecessary dynamic casts.  Seems to slightly improve performance with sorting.
There are some more places that IComparable checks can be cached, but they don't seem to improve performance at all.

swoolcock/diddy,swoolcock/diddy,swoolcock/diddy,swoolcock/diddy,swoolcock/diddy