There may be harm in divulging your .htaccess file. This is usually one of the reasons why there's a rule to block access to .htaccess, like this:
Deny from all
The contents of this file may tell users about your configuration, such as where passwords, certificates, and so on reside in the system, and how various physical directories map to virtual directories, etc. It can expose more about your system then you'd like a typical person to know, and definitely more than you'd like an adversary to know just given to them on a silver platter.
While there's technically no harm from the file itself (as long as users can't modify the version on the server), the .htaccess may give malicious individuals information on how your system might be vulnerable. Do feel free to share this file with people you trust if you need help with it. Sending it by email is still safer than using a public forum if viewers might be able to associate the file with your domain/server, but I'd recommend physically delivering it (in person!) on portable media if it's reasonable to do so (e.g. sharing it with a colleague you see at work every day).