Well we all have different opinions . Funny old world if we all thought the same eh?
Indeed. This is what I always say to my kids 
Fwiw, I don't think there was an agenda but I will say that the judging has been more erratic this series.
I also thought, that since Jamelia, it had been agreed they would give a clear reason for their save/preference based on that DO only not the whole series average or their potential or better dancer but just had a bad week. In fairness, Craig did say 'better finishes' but I am not clear on what he meant by that, having watched them both back.
As to series 15, in fairness the judges ranked the four in the following order:
Alexandra 119
Joe 118
Debbie 117
Gemma 114
Their votes didn't count - public had already put Alex in the DO twice incl the quarter finals, as she was marmite to some. Debbie wuz robbed was deemed a ringer too and was in one DO. Gemma wasn't as good as the others and was in one DO. So Joe was the last man standing by default and was popular. Plus a lot of affection for Katya post-Ed pre-Seann (and there had been some stand-outs - the silly AT lift, the cabaret samba etc)
The jury weren't biased on the night - they thought Alex was the best dancer, including Craig who was close to Joe allegedly.
They never had to save Joe as Joe was never in the dance off.