There's a subtlety to the guidelines for editing here that many people (even some aged, veteran users) don't quite pick up on... So I'll try a different approach here
There's a famous interview with Richard Feynman, where he was asked the question, "how do two magnets attract or repel each other?" To which he responded,
I can't explain that attraction in terms of anything else that's familiar to you.
...and then went on to list how he might answer the question if someone else were asking it. This is a brilliant response, precisely because it illustrates a consideration that so many educators skip: understanding the intentions of your student.
The basic guidelines for editing are listed on the full edit page:
Note that they say nothing about the "intended" meaning of the post; you're expected to clarify the meaning, which you can hopefully learn by reading the post... but the only way to know if you've preserved the asker's intent is to make the edit and see if he's satisfied with the results. When in doubt, talk to the author: a comment paired with the edit expressing your intent and requesting feedback on your edit can go a long way toward ensuring that your edits are helpful.
The critical guideline here is always respect the original author: edit with his best interest in mind, strive to make him look good, write a question that'll get him the help he needs!
Watching some editors debate this reminds me of an old story...
He also who had received the one talent came and said, "Lord, I knew you that you are a hard man, reaping where you did not sow, and gathering where you did not scatter. I was afraid, and went away and hid your talent in the earth. Behold, you have what is yours."
But his master answered him, "You wicked and slothful servant. You knew that I reap where I didn't sow, and gather where I didn't scatter. You ought therefore to have deposited my money with the bankers, and at my coming I should have received back my own with interest. Take away therefore the talent from him, and give it to him who has the ten talents. For to everyone who has will be given, and he will have abundance, but from him who doesn't have, even that which he has will be taken away. Throw out the unprofitable servant into the outer darkness, where there will be weeping and gnashing of teeth."
— Matthew 25:24–30, World English Bible
It's always safe to edit a question in a way that does not change the literal meaning; after all, who can criticize you when you haven't done anything? But when you do understand the intent, and yet, out of an overabundance of caution, do nothing to alter the meaning even if by doing so you could better reflect the author's intention and potentially provide a way for him to obtain assistance here, then you're hardly respecting the author; like the cynical servant or a weary teacher who no longer cares if his students can absorb the information he regurgitates, you've wasted an opportunity and squandered the attention of your audience.
When you edit a question, or when you review the edits of others, ask yourself this question: does this edit make it more likely that the asker will obtain the information he needs? The answer you give yourself to this question should provide you with a foundation for any discussion that might follow from it.