Originally Posted by cavit8

Most chain pins are peened so if you use a chain tool you shear the peening off ( ) and the pin won't reseat properly. I tend to use the magic link thingy and just drop links as needed. Brief blurb on peening and shearing here
http://www.parktool.com/repair/readhowto.asp?id=25

Oh, and I'm feeling happy if a little poorer.