Moreover, most physicists (those who don't have particular expertise in information theory) are not particularly qualified to evaluate the subject except, of course, as intelligent laymen.
I never seen a pro cryonics argument that actually relied on information theory.
Even cryonics proponents would generally agree that you won't leave enough information if you boil a head in a cooking pot for 2 hours then freeze it. A valid pro cryonics argument must concern specifically the chemical damage (and loss of information stored in the chemical states), and distinguish between cryonics and hypothetical "boiling then cryonics". edit: that is to say, before information theory enters consideration, you have to deal with chemistry and physics enough as to not be making a fully generic argument that is equally applicable to the hypothetical "boiling then cryonics".
All such 'expert' testimony that is dragged up here over and over has included claiming that cryonics cannot work because it is not possible to repair preserved neurons in place.
And when further asked about actual information content, they tell that they do not think information is preserved either.
Since this is not remotely how cryonics works
That's how it is generally advertised, so this is what they are going to opinion on before they are actually informed of your specific variety of cryonics belief.
Since this is not remotely how cryonics works whatever dubious claims to authority that they may have had are screened off.
Yeah, except you're the one who were trying to argue by authority in the first place.
In the past, the Cryonics Institute has had a policy that said that they would not accept anyone who is not a member. This has changed. The policy now is that someone who has full legal authority over your body can sign you up after you die. It costs $36,250 to be frozen if you are not signed up, which is more expensive. They also will not do anything until you have been on dry ice for 2 weeks after they have been contacted, so not being a member is more risky.
This is very important news for anyone who is currently cryocrastinating. It means that you can drastically increase your chances of survival without filling out any forms. All you have to do is tell a loved one you want to be frozen upon death, and that you would like them to take responsibility for making sure this happens. This takes literally 30 seconds. Do it now!
This news might also be a reason to not sign up right away, if you think something better (like radical life extension or uploading) will come along in your lifetime. We should discuss this in the comments.
Edit: The general consensus of this discussion is that this is a really bad reason not to sign up for cryonics.