There's a lot -- and I do mean a LOT -- to be said for "feel".
Sometimes you are actually getting a great sound out of a pickup (or guitar/rig/etc) but because you have to alter your technique so much to GET that sound, making the act of playing so laborious that it is unpleasant, it "sounds" terrible to you.
Then when you just hand your guitar to another player (especially one who plays with a similar style/attitude) and sit and listen to him, you're stunned at how great it sounds. This is because you no longer have the ball-and-chain of laboring to get that tone to distort your perception of the sound -- you are now just relaxing and listening with a more objective ear.
The ideal pickup is one that will get you THAT SOUND without you having to alter your playing technique and otherwise dig in and work so friggin' hard for it, one that complements the way you physically play the guitar rather than fights it. Then you play more fluidly and more relaxed, and you play a lot better because you feel like you can do just about anything.
To a listener, even another seasoned, serious guitar player -- or even to an ocilloscope! -- there may be no significant difference in the tone. But to the player, it's a universe of difference that gives him wings...