Never heard such rubbish as clipping removes the shine.
I clip October time and two or three times during the winter as the horses are in full work. As soon as their winter woollies are off they shine.
I rarely body clip in the summer -the weather is not that hot in the UK and there is no need.
I did have a pony who had Cushings which meant she always had a very woolly coat and I would clip her in the summer and she always had a shine when it was off.