Yes, changing your password via Steemit will change your account's permission keys essentially. The keys are derived from a combination of your password and your account name.
If you believe your keys or password may be compromised, it is a very good idea to change the password, so long as you back it up and put the backups in secure and safe places, just like your original password.
I think that answers my question too then. There's no way to change the posting key (for example) without changing the password. Thanks.
You can do this with Steem accounts if you're a power-user type and aren't shy of a command line interface. With the steemit.com GUI, it's no longer possible.
Changing one key will make your original master password not function for that particular use, so if you used something other than Steemit to change just your posting key, the password would no longer allow you to post/comment/vote.
Oh thanks... that's interesting. I'll get into more of the details of the CLI and APIs soon I hope.
Thank you very much!