I have been saying it since July 4, and will repeat it again -- Nash won't make Gasol that much better.
Gasol's problems stem more from his mental weakness and physical softness than from his declining athleticism. Nash won't help Gasol rebound better, or not play matador defense against Cousins, Z-bo, Dirk, Bosh, etc. Gasol lost two easy rebounds to Rudy Gay and Speights.
Also, Nash won't help with Gasol's fumble-itis.
In fact, Nash may make Gasol markedly worse -- emphasizing that Gasol can't be relied upon to hit big shots at big moments or to make good decisions with the ball in pressure situations (like we saw last year against OKC, and this year against the Spurs, etc.). The more pick and pops and pick and rolls Nash sets up for Gasol, the more he will miss the Js and get swatted at the basket or miss pressure free throws.
Lastly, we see Kobe play pick and roll with Gasol ALL THE TIME. Last year, game 4 against OKC, we are down 1, last minutes of the game, Kobe runs a beautiful pick and roll with Gasol. Bounce pass as Gasol rolls. He catches it cleanly and is 12 feet from the basket. He can (1) dribble aggressively right into help-defender Ibaka to draw the foul or try to finish off the glass over him; (2) shoot the WIDE OPEN mid-range J (since Bynum is by himsel on the weakside for any long rebound); or (3) take one simple dribble to make Ibaka step out just a litle, then lob it easily to Bynum for the slam (and to likely win the game). What does he do? None of the above. He makes no play. Doesn't force Ibaka into a bad situation as the help defender. Doesn't shoot it. Instead, as the WIDE OPEN ROLL PLAYER with an open lane to the basket, he decides a cross-court pass to.........World Peace!!!????
Durant steals, layup, game. Kobe called him out after the game and was obviously ticked off about the continued playoff slumping Gasol. Nash won't fix that...lack of heart and clutchness. Gasol DOES NOT WANT THE BALL in those situations.