Oh dear - never use it to log in? what??
*When you create your account you should immediately save the master key on a document and store it on a usb key. Also write it down by hand and store it in a safe place. This is the only key you have at the moment and Steemit will ask you to use it to login so you can access your other keys. Be 100% sure you have done this step correctly before moving on.
After completing the next step you should keep this key offline. You can not have enough back ups of this one and you should never, ever use it to login! This key is only needed to regenerate all new keys and if your account gets hacked you will need this password to attempt account recovery.* Steemit Passwords / The Ultimate Guide To Key Safety
I still don't know the master key from the P_etc password.