Hmm. Not really. Not if you're comparing apples to apples. In other words, if you cook a brisket as usual (till done), cool, fridge, then reheat by the method to which you refer, I think you'll have good brisket.
If you cook partially and finish later as described in the OP, I think that as long as you don't cook too long, i.e., take it past tender to the pot roast-y stage, you'll have good brisket. I would not finish to 200, necessarily, I'd finish to tender, whatever that temp. Could be 200--but maybe not.
All this said, I'd really have to try the method in the OP to see how it goes. If worthwhile, it would be worth looking into for make-ahead situations, Q-joint scenarios, possibly catering.