8 ohm speaker hooked up to 4 ohm post ?

I read that a gentleman switched his speaker wires from the 8ohm speaker post on his Amp to the 4ohm post, and enjoyed a healthy change in the dynamics of his music. I don't know what ohms his speakers run on, but I have an 8ohm pair of Meadowlark Shearwaters. I would like to try this, but am afraid it could harm the speakers and/or Amp. Can someone out there tell me [for sure] what will happen?