Ok, here's the deal....
Wyvern is the result of several very large corporate flight departments who use charter operators on a regular basis, getting together and setting some standards that they want to see from charter operators in order to secure their business. Many of these flight departments used to audit charter operators themselves, however, that was time consuming, and frankly, was a pain to many charter companies having sometimes as many as a dozen audits each year.
Once a year, these flight departments get together with the charter operators and the Wyvern auditors to discuss standards, set policies, and review what does and does not work. I'll agree to a single point: some of the requirements the flight departments have come up with are somewhat onerous. But, by and large, the system works and has given these flight departments peace of mind in using charter companies that they themselves have not been able to personally audit.
For charter companies, receiving a passing grade from Wyvern can result in business that they otherwise would not have. For others, it reinforces that they do things the right way (i.e. not cutting corners, providing competent pilots, and maintaining their aircraft to the highest possible standards)
Let me point out that Wyvern and ARG/US are totally independant and different. Just about any charter operator can pay ARG/US, and with minor internal changes, can receive their blessing. Wyvern audits are paid for by the flight departments - not the charter operators - and avoids the conflict of interest inherent in the ARG/US system.
Now to the points made about aircrew approvals: yes, Wyvern standards can sometimes seem unreasonable. However, and this is the big point, many pilots who are not able to check every single Wyvern box, CAN and DO get approval to do trips for the flight departmens if they are given a chance to review the pilots qualifications and decide independantly of Wyvern, that they are ok with that pilot flying their trips. In other words, the Wyvern standards are rarely set in stone.
I know these things because I have worked as a pilot and manager for two charter companies that rely on the Wyvern system to fly trips for the flight departments who use the Wyvern report. I have also personally participated in the yearly meetings in which operators and flight departments meet in person.
The Wyvern standard is not perfect. With that said, it's my opinion that it is far more comprehensive than the other auditor companies out there. The bottom line is that it's up to the charter company management and sales staff to evaluate what is gained by participating in the Wyvern process, and to raise their standards of operation to secure a lot of business from the Wyvern subscribers.
From my perspective, it's a small price to pay for thousands of hours of charter - even if it temporarily disqualifies some pilots on certain trips.
By the way, I do not work for Wyvern, nor am I currently working at the charter companies I mentioned.....
Sorry if I was a little harsh on AZ Typed and Stealth21. I hope this explanation has cleared the air.