My signal went down. I tried it and watched the Debug screen. It seemed to force it to change to another site in its Neighbor Set. It only forced the EVDO to change, not the 1x.
So I suppose if you are stuck on a farther away site, then doing this may move you to a closer stronger site. However, the benefit of this is probably nil. Because if you are on a farther away site, it probably has a better EcIo ratio, and thus why your device is keeping it.
Robert