Hotshot-Tottenham
Edgar Davids
That might be the letter of the law, but the currently accepted and enforced interpretation of it is different.
If the letter of the law was followed very closely defenders could benefit massively by having their arms out from their bodies to "accidentally" block the ball without intentionally handling the ball. John Terry was an expert at throwing himself into blocks with his arms outstretched and gained clear advantages at times even though he didn't "intentionally handle it".
That's where the 'unnatural position' comes into it.
Trying to block, whilst grounded with outstretched arms would certainly fall into that category.
But you use your arms for leverage to jump, so for arms to be in the air just prior to leaving the ground would be natural.