The main problem I have with this kind of argument is that there was plenty of "embarrassing" stuff left in there. Why not take out the stuff about Jesus praying to God before the betrayal? Or continually depicting the disciples as dense? Or Jesus name calling and losing his temper? And so forth. If they were gonna try to clean things up, why didn't they go the whole way? And if Christians were worried about explaining away embarrassing things, then why did they choose to include the earlier Gospels in the canon? If things are as the argument says, and Christians tried to rewrite the story to wipe away potentially embarrassing stuff, then why did they put the first version of the story right next to the supposedly modified ones?