Does Desean Jackson still have deep speed?

Not once during the pre-season have we seen Desean get separation deep. Is this because he only plays hard in games that count? Has he shown the ability to get significant separation on deep routes in practice? Earlier in his career he routinely got multiple steps behind the corner or safety. I was hoping to see that in pre-season and am now starting to get worried that he might have lost a step. Thoughts?