I gotta agree with Dennis. If you pass, it is a non issue as nobody is going to notice or care, but if you don't, then letter or no letter you are still going to cause a commotion and hard feelings. As to workplace issues, yes, if employees have known you before the transition process and have watched you in progress then they know whats afoot and yes, it's nice to have documentaion that you are for real and not just some flaky guy wanting into the womens room, and yes, it does make a difference who's in which, like it or not and all pylosophical issues aside.
In the workplace, letter or no letter and legal right or not, one has to consider the feelings of the people worked with and what that is worth to you. I know that in my workplace where they have watched the whole thing over the last few years, there are still a few women who think the whole idea is atrocious and even though my documentation comes from our companies own psychs it just isn't possible and will always feel I'm male, regardless of the consistantcy and opinion of other workmates and would fight to keep me out of the public ladies room if I cared to use it, but because we have non gender rooms in public areas and in every Med unit, I simply use those instead to prevent conflict until surgery at which time I could tell any person objecting to fly a toilet paper kite as at that point, I will be no different, which I can't really say at this time with the evidence hanging down. Actually, nothing is stoping me right now other then regard for the feelings of others, even if they don't accept me as female and the fact that with the non gender rooms, no point in pressing the issue with them while still pre-op. As far as company policy and california law though, I can do as I please.
In strickly public areas off work I used to use mens rooms if the boys liked it or not, but these days womens rooms are ok with me as what they don't know won't hurt them and if anyone were to question anything, ALL my identification is in female name and gender. I did get letters for my workplace right from the start and have periodically had them updated, just for my department manager and personnel files so he can field any complaints about me, but there have been none now for the last year or so, but in the beginning, he was constantly flooded with phone calls about me and what the hey was going on?
And hey Dennis, YOU would get into trouble entering a Womens Room ..... All the ladies would be asking to borrow my "Brick" if they don't have one themselves ......
Terri