Reversing the "words" of a container with a bidirectional iterator
Although not relevant to the algorithm itself, you could still consider these basic things:


It's best to use "\n" instead of std::endl for newlines.
You don't need a return 0 at the end of main(); it will do this for you automatically.
You should also add curly braces in my_reverse() for consistency and in case you'll need to add more to the loop.
The name IsSeparatorTester issep seems odd as an argument. Perhaps it should be renamed to something like Separator sep since it's not performing an action (like a function) and should therefore be a noun.

However, if you're mostly trying to reimplement std::reverse(), then you can leave it out this argument altogether.  There may not be many cases in which the user would choose something other than a space as a separator.