Not exactly, as the thread you link points out you can reference an image ID in FROM rather than the name:tag which has potential to change silently.

It's the equivalent of using a package manager against a repo you don't own without pinning - expect problems.

This can be mitigated by FROM'ing via ID or avoided entirely by running your registry where tags are reliable.

Admittedly, these things are not necessarily obvious, but I think it's a bit disingenuous to paint Dockerfiles as worthless or broken.

That said, ShutIt looks very cool and seems to address exactly some of my concerns / desires about working with Docker.

I just don't agree with framing it in opposition to and at the expense of what exists.

There's value in a container description that is fully self-contained, transferable and 'dumb' enough to be transparent.