Kurt Seifried of the Red Hat Security Response Team reports: A number of unsafe uses of /tmp, ranging from actual code to test code and documentation exmaples. In general many are due to unsafe use in bash scripts, and can be fixed by using mktemp() correctly. There is also at least one Ruby one (the Vagrant file) and several go scripts that use bash command lines unsafely.
Under 1.5, I deleted /tmp, started the docker service, pulled an image, and started a container with no mishaps or creation of /tmp.