I wonder what the policy is on answers involving ppa's.

This question came to my mind, especially after reading many answers on Tor-Browser related questions. In most of these answers, like this tor browser install Ubuntu 14.04 a ppa is recommended. Yet in the comment to the accepted answer my problem with these solutions is clearly stated.

Is there any policy you folks have already developed?

To me - thinking about quality on this page - it appears to be a problem, when there are answers - especially regarding security critical software - that involve ppas.

What are your thoughts or solutions?