First of all, roots from Cyms are technically roots, not rhizomes as in some orchids. I have seen a very short rhizome connecting the pseudo bulbs but very, very seldom.
Secondly, meristematic tissue comes only from the growing node on a newly formed growth taken when the growth is up about 3". To my knowledge, no other part of the plant will work.
And thirdly, the reason that growers went to mericloning plants was that it was CHEAPER not more expensive. It led to faster maturing times, there was no need to weed out poor quality (except for the runts), plants could be released before they bloomed if necessary and a known product was the result.
The statement that you will be getting an "outstanding example of an orchid flower" only refers to the fact that the grower feels the plant will be a good sell on the market for color, productiveness or other general characteristics appealing to the general public. I have seen many mericlones I would not make room for in my collection primarily because they are not of the quality I personally am looking for. I also like to have unique plants others do not have.
Cym Ladye