Excellent posts! Ive learned more on this one topic than i could have studying for a month! While reflecting on the subject at hand, i think the other reason the JW's make such an issue about the instrument of execution,(besides trying to distance themselves from everyone else) is the fact that the cross as we know it in the form of the letter "t" was reminiscant of the god tammuz. (at least thats what i was always told as a JW) and it would be unthinkable for God to allow his son to be killed on an object that represented a false god.
But what they fail to realize is HELLO!!! the ROMANS WERE PAGANS!!! They borrowed this form of execution from the pheonecians who were also pagans. Of course God is going to let wicked, pagan people kill his only son, have a murderer be released (barabus), have his garmets gambled over, be spit upon, then hung between two thieves, but stop the executioners from placing him on a upright pole that contains a cross piece.
Again, (in my opinion) im not saying it was definately a cross, although i think the evidence strongly favors it. Watermelon, i think the biggest question you need to ask yourself, is not what did he died on, but what he accomplished, and furthermore, why do some religious groups--no names mentioned...haha make such a big deal over it. What is thier motive? Is it a pure motive? A desire to get to the truth? or a political agenda?
Someone mentioned earlier in this post about Thomas telling Jesus "unless i see the print of the NAILS" indicating there was more than one nail used. (John 20:25) I dont think this was mentioned, but in Matt27:37 it says "Above his HEAD they placed the written charge againts him: THIS IS JESUS THE KING OF THE JEWS" It would seem without a cross piece, the written plaque would be over his HANDS, like the WTS always picture.