"[C]ompanies may be relieved that gathering the numerical disclosures that would be required under the rules proposed by the SEC will, for the most part, involve adapting and repurposing information that is already being gathered and used for other reporting purposes. However ... it may be challenging to provide useful and informative descriptive disclosure about the relationship between compensation 'actually paid' and 'financial performance' (as each is computed under the methodologies prescribed by the proposed rules), as well as the comparison of the company's [total shareholder return] to that of its peer group."