Insincere because the question has been answered repeatedly. Snowden isn't going to release any of it. The parties who possess the full cache of Snowden documents (Greenwald, Poitras, and Gellman) actively do and will continue to report on the documents when they have had enough time to understand them, responsibly vet and redact potentially dangerous or harmful details, and offer the Government the opportunity to comment and request (almost always in vain) additional revisions/redactions. In addition to these 3 individuals with access to the complete set of documents, other large news organizations have also been given large subsets of the documents. Numerous other journalists have been given unfettered access to search the documents on location (a compromise to keep copies of all of the documents to a minimum). There are many unconnected entities now with large copies of all kinds of information, and new stories are being broken constantly, but you have your "sincere reservations about it".
What are your sincere reservations, if I may ask?