Exactly a key reason I chose to avoid a biscuit joiner... but others will explain that is due to user error, not allowing sufficient time for the moisture in the biscuit joint to equilibrate with the surrounding wood before sanding and finishing the piece. Later, equilibration does occur and the loss of moisture from the region overlying the biscuits shrinks, causing the "telegraphing."
That's definitely true but isn't the whole story. One of the things that I really like about the domino is that I can dry fit complete cabinets and check everything before it gets glued together. I'm in the process of building a pair of doors that will be almost 4' wide by 5 1/2" thick that will be a bookcase for paperback books as well as doors for the closet. If I had used biscuits instead of dominos I would not have been able to dry fit the the bookcase and actually hang it from the hinges (w/ no clamps, screws, glue, etc), where I discovered that I had miscalculated the clearance required to swing one door past the other.
Since nothing was glued it was a simple matter of cutting the shelves an extra 5/32" shorter. I don't know how I would have fixed it if everything was already glued together.