There are too many factors involved with your final products' potency, and in a perfect world you may be right. I'm doing this to experiment for my own enjoyment, and to further learn the basics of growing cannabis. I didn't even think to take clones from it my first time around because I didn't really plan on setting up a grow room.

But think of it this way... lets say you could measure the conditions of your growing environment on a scale of 1 to 10, 10 being the most perfect conditions. So even if you lose potency from revegging and the first time it grows the conditions are at a 5/10. Then after you reveg and learn a little more about it you can alter the conditions to a 9/10. Where will the better bud come from?

At any rate this is no more than a hobby to me. I only do this because I enjoy the experiment, and I don't rely on having a perfect finished product for any reason.