Michie says that the client drawbacks to this method are minor. Yes, clients may get reports directly from the engines saying that they're "not using ad groups correctly," and at times, it may be difficult to for them to find specific keywords or phrases within the accounts. But the benefits of making swift copy changes across multiple campaigns (without having to break up and recombine ad groups) as well as not constraining bidding according to predetermined, sometimes arbitrary, groupings outweigh the cons tenfold. Besides, with full service campaign management, clients are welcome to dig into any of the accounts they'd like--but they shouldn't need to.