There is no right or wrong here IMHO - different approaches work.
I wouldn't advise Alex or Marcel Cairo to present things in the same way. I've listened to Marcel's programme, it is safer, more conventional, nothing wrong with that. I enjoy listening.
Alex approach is more provocative and confrontational and I think that is great, I think that in today's world, with the success of CSICOP, JREF, COPUS, it really has to be. Trying to convince skeptics with data or logic isn't enough.. it hasn't worked in past ...... one either lets them get away with misrepresentation or confronts them.
As for 'tone' .... I mean who would have advised Randi to take the approach he took? He is hardly charming, sarcastic, rude, grumpy as hell, the guy hasn't done proper research, has tested far less numbers than he claims, has chosen easier targets, avoided conducting long term trials ......yet people accept him, they got used to him, I even like the old fox Randi too
... because is sometimes right, sometimes funny .....but the problem is 'skeptics' rate him as an expert or trust his viewpoint - they shouldn't. They are impressed by his incredible confidence. In fact the whole 'skeptic' movement is based upon misplaced confidence in others with confidence.
If Alex and others provoke skeptics to actually read properly the other side of the debate, who knows it might get the scientific debate into the mainstream and get a few more scientists to give their opinions on the quality of psi research in public, organized media skeptics motives, rather than just express these in private in fear of ridicule