I'm asking about this question. I posted my answer a while ago, containing only the final result and a hint about where to search for a proof. I intended that I would post the full proof later, but actually never got enough time and enthusiasm to do that.
Now, another answer is posted and accepted, containing a correct full proof leading to the same result. The approach shown in the answer is basically the same that I used when I derived the result, so it would not make much sense now for me to post a duplicate solution.
Now my answer looks kinda useless and redundant. What the best thing I can do with it now? Should I delete it, or leave as is, or anything else?