Question: Basically I was looking around the queue and found this suggested edit: 
<https://stats.stackexchange.com/review/suggested-edits/117203>

It became obvious to me the user was having difficulties with the account(s), so he posted an update with another account as an edit.

The suggested edit was approved (not by me, I skipped it). But I can see reasons to actually reject it. The user should be asked to merge the accounts first. We should treat the edit as if it was another user.

Why? Because it becomes too simple to vandalize posts doing this. I've never seen it, but it became obvious to me after seeing people posting updates with multiple accounts how easy it would be to pretend you're another person and suggest an update, and how it would easily pass in the queue.

I've seen it reported in meta before, so I'm posting this thread as [discussion](https://stats.stackexchange.com/questions/tagged/discussion "show questions tagged 'discussion'"): should these edits be accepted before accounts are merged?

I want to know it so I can act accordingly in the review queue.

New example: [Develop Prior from Previous Studies using Bayesian Updating: Poisson-Gamma Example](https://stats.stackexchange.com/questions/236439/develop-prior-from-previous-studies-using-bayesian-updating-poisson-gamma-examp)

Answer: 
I agree with @amoeba: it's important that authors have the ability to update or improve their question as quickly as possible. Otherwise it may be closed as unclear, or answers that do get posted will fail to address the author's main concern. We have many ugly, hard-to-follow threads that are a nightmare for future readers, resulting from substantial updates or clarifications appearing after some answers have already been given. It is certainly worth trying to prevent this.

I frequently approve such edits. But I also post a note saying:

> 
> Please register & merge your accounts (you can find information on how to do this in the **My Account** section of our [help center](https://stats.stackexchange.com/help)). Then you will be able to edit & comment on your own question.
> 
> 
> 

Copy-and-pastable text:

```
    Please register &/or merge your accounts (you can find information on how to do 
    this in the **My Account** section of our [help]). Then you will be able to 
    edit & comment on your own question.

```

Clues that this is what is going on:

* The question is recent,
* Both the original account and the editing account are new (or the edit is anonymous, which indicates the author has logged out - I would post a slightly different comment in that case, suggesting that the author should log in),
* The edit contains a clarification, or adds some information that only the original author would be expected to have.

It strikes me as remarkably unlikely that a new question with fewer than a dozen views not only will be stumbled on by a random visitor, but also that they should have mistakenly attempted to edit and improve it.

If I ever get a confused comment from a surprised poster wondering why somebody else has edited their question and reslanted it with their own additional information, then I will know I've made a wrong call, but it hasn't happened to me yet!
(Take this as personal opinion speaking as an ordinary user)

If it's an edit you'd accept if it was from a different user - an improvement without changing the intent too much - you could accept it whether or not you were sure it was the original poster.

However, if it actually is the original poster suggesting an edit from a second account, I regard the merging of accounts as generally more important to fix first -- this is so we're not running around after the same person doing it again 20 minutes later and again an hour after that. If we do what they want (accept the edit) but rely on them to go to the trouble of merging when they can get things done by making us run around instead, why would they? 

[Sure there are well-intentioned users who will do their best, but many people are lazier if they can be.]

So I'd suggest using some judgement -- while it's good to get questions improved quickly, it's also important avoid the OP continuing to suggest a number of further edits from the second account (or a third...) instead of merging.