I wonder why your speed
I wonder why your speed decreased that much. I mean, sure, they don't have all the padding of traditional boat anchors, but they still offer some protection.
For me, it took me over a year to get my speed back once I gave up the shoes, but then I even got faster, and no I'm not saying running barefoot had anything to do with it, it may have and it may not have, the jury is still out. But I took 15 minutes exactly off my half marathon time from the last time I ran a shod half marathon to the first time I ran a barefoot half marathon.
Now that I have had surgery to correct Morton's Neuroma in both of my feet, once I've healed and gotten some fitness back, I really plan on testing this out. I can't wait, but I'm not holding onto any high expectations either.
It'll come...be patient. ;-)