Welcome to GitHub!  :-)

All things being equal, it would be nice if const was the default and mutable was explicit.  But this is a case where I think const just makes the code longer without a benefit in proportion to the extra characters.

I mention this because Carl is a `const` skeptic to begin with, and I'm trying to get a pull request in that's based on what I consider to be an important case w.r.t. undefined behavior:

https://github.com/rebol/r3/pull/72

So in the spirit of maintaining a sense of perspective regarding the usage of const, I'd encourage you to remove these!