The Opening of the Mouth is really only necessarily for priests. Most Kemetics don’t perform the OotM, and I don’t have any intention of ever doing it to my statues. If the gods wish to Open the statues on their end, that’s fine. But I won’t ever do it myself because I’m not a priest, and I don’t intend on becoming one XDD
I would bet that each Kemetic has a slightly different version of the OotM. KO has their own format, and Reidy’s book lists another. I also think that Wisner’s book has a format of the OotM (likely based off of KO’s, tbh). So in the case of temples (Reidy’s temple and KO), the method will be uniform as dictated by the group’s rules and stuff. For those of us who are not part of any official group, we’ll likely pull from whatever sources can be found, and there may or may not be slight modifications made to the ritual.
If I were going to perform the OotM, I’d probably pull from Reidy’s format, because I trust it more than Wisner’s. I personally wouldn’t deviate much from the rubric, as I don’t believe that you should deviate when it comes to the OotM. But I can’t speak for other Kemetics or what kinds of deviations or different methods they’ve used for Opening their statues. Also doesn’t help that I can probably count the Kemetics that I know that have Open statues (outside of KO) on one hand. There aren’t very many that go through with it because 95% of us aren’t priests, which means that the “sample size” is really small, and therefore hard to gauge how many different versions of the OotM are performed.
So… yeah. idk if that helps.
Basically don’t do it unless you’re ready to care for that statue FOR THE REST OF YOUR LIFE, and maybe make arrangements for it even after that. Remember, if you forget a house plant, it wilts. If your forget to feed your dog or cat, they will probably remind you. If you have a child, they will cry for attention. Sometimes gods will nag you when you forget, but you can’t count on that.
My statues aren’t open because I have no illusions about my ability to remember to do stuff every single day. You can still talk to gods without an open statue.