Political debate advice

This evening, the political debate session begins.  If I were a political advisor, I would offer  advice to each of the candidates,

"A good leader can engage in debate frankly and thoroughly,

knowing that at the end he and the other side must be closer,

and thus emerge stronger.  You don't have that idea with you are arrogant ,

superficial and uninformed."

Nelson Mandela

At tonight's debate, the candidates are more likely concerned about focusing on their  accomplishments rather than seeking common ground with their opponents.  

I would encourage the candidates to be concise, factual, thoughtful, and charming. 
Do you think this is good advice?