Yes, they can. Several of our silvers are using it. The only chat restrictions I know of happens during the first 20 hours if playtime to prevent spam. As far as I know that only affects PMs and even that time you can shorten if you ever made any kind of purchase (C-Store, game copy or subscription).
Basically I held a speech thanking everyone for their commitment to he fleet and making it what it is today and then getting relieved of command by Trek using the original Ceremony from Chain of Command.