Diminishing Returns

What happens when an established superstar joins a club with no defined role for him? When David Beckham joined a Real Madrid team that already had Luis Figo manning his position in 2003, the result was an awkward tactical squeeze made to accomodate the talents of both players, thereby diluting the very qualities that made those players effective in the first place. The same occurred when Michael Owen joined Los Galacticos late in 2004; on a team stacked up front with Raul, Ronaldo and Guti, he went from world-renowned striker to super-sub, eventually opting out to Newcastle United for the chance to play first-team football. Andriy Shevchenko and Michael Ballack, anyone?
I'm not predicting the downfall of Thierry Henry, mind you, but it should be fairly evident that at this stage he is a square peg trying to fit into a round hole. How can Frank Rijkaard fit Titi into an attack that already features Ronaldinho, Eto'o and Messi without diluting Henry's unique abilities? For all of his winger-like qualities, Henry's time at Juventus proved that he is not cut out for that position; his at-times awkward play for France suggests that he is not suited to play as a single striker; and let's not even get into the question of who will sit for Barca to accomodate their superstar signing.
Even so, the question of who will sit remains at the core of all of these big-name signings, because in the end it is the fans who lose out. As terrific a story as their transfers made, watching Shevchenko and Ballack struggle for Chelsea robbed all of us of a chance to observe their previous brilliance, particularly since their talents are so rare that there is no one to fill the void left by their departures. Beckham's resurgence has been so uniquely tied to the fact that Real Madrid, having divested itself of much of the superstar dead weight that preceded him, now had to rely on his abilities rather than simply accomodate them, that talk of him being "only good on set pieces" has dissipated. Of course, to get to this point we had to endure three years of "Galacticos" stepping on each others' toes while trying to make nice with each other.
Thus it is that from a fan's perspective, we don't really win; if Henry struggles, well, that sucks. If he's great but Eto'o has to sit the bench, where are we going to find another Eto'o? If Messi gets lost in the shuffle because there's not enough of the ball to go around, how is that any fun? What happens if they all start infighting (like Barca started to do this season)? Do we really want to see Ronaldinho, rotational striker?