What worth is CSR Assurance?

Recently a report came out about assuring CSR reports (i.e. verifying that the information in the reports are true) which was funded by CSR Assurance companies (hmmm), saying that not enough companies are assuring their CSR reports (surprise, surprise).

I would like to proffer that CSR assurance is actually pretty pointless and useless (in of itself) because:
1) How much time or effort do any of the assurers put into looking at any of the data to see if it is true; is it even possible to verify half the data anyway?
2) Is there any legal liability for assurers, like there is for assuring regular financial reports?
3) Does the assurance mean anything to the reader at all, or add any value to a CSR report?

Question 3 is rather interesting, because the best CSR reports now include all kinds of other methods of assurance, though not technically 'assurance' which for me are much more interesting and useful. These include comments from concerned employees or customers, (unedited) comments from critical stakeholder councils and even comments from a CSR expert on whether the key Reporting principles have been followed or not (e.g. GRI has several principles including materiality). Others include reports from SRI experts or other relevant shareholders.

All of these comments mean more than a statement that the numbers are correct, which i truly doubt, since many of the most important numbers are hard to measure and the rest rely on self-reporting from the company anyway (rather than some auditor going across the world to check on what the exact waste is from any particular machine and whether that is what it has been claimed to be).

So, nothing wrong with assurance, but i do not think it adds much value to a CSR report for external readers, and probably does not (in of itself) help a company improve itself internally. At least, in the press release, they admit that the quality of assurance varies widely, and also point out that many of the assurers are also the ones who help prepare the report!