Keep the version, whatever it is. The "check of ports" is annoying, because some of these checks may be in scripts and happen at runtime for ports.
The way it usually happens is: something breaks -> porters don't have time to check too closely -> someone moves the ports to using gnu grep instead. I had rather we had as much stuff as possible working with the base system. Having --version is not a problem. Not having it will probably break things, and we will probably notice six months from now.