After someone published Aug 2013 material, it was clear that Snowden isn't the only one. There's no harm in talking about two whistleblowers at that point. Emp

After someone published Aug 2013 material, it was clear that Snowden isn't the only one. There's no harm in talking about two whistleblowers at that point. Emphasizing that there's more than one might encourage even more whistleblowers. Talking about a certain number might also hide that there are even _more_ out there. Knowing the exact number of sources might help the agencies assign publications to sources, and thus, support in locating them. If you try to assign material that is actually from five sources to just two, you'll have a hard time seeing a clear picture.