Nothing conveys emotion like a perfectly timed string bend. It can help phrase a solo, or transmit wild emotion. Just listen to those Stevie Ray Vaughan tracks, like Tightrope, or those Gary Moore songs, like the wonderful Still got the Blues or Clapton's subtle Wonderful Tonight. The Key to String bending is hitting the pitch accurately, otherwise it becomes less music, and more castrated cat!
The way to hit those bends is to:
(1) Develop an ear for pitch accuracy
(2) Finger Strength.
The best way to do this is when you practice bends, play the actual note you are trying to bend to. Then keeping that note in mind go down and bend the string up until you reach the pitch correctly. Let's take the following example:
E-------------------------------
B-------------------------------
G--12-----10^(12)---------------
A-------------------------------
D-------------------------------
E-------------------------------
The 12th fret (G) is the note you are aiming for, the 10th fret is the starting point. It is absolutely fundamental that you hear the note you are trying to bend in your head or be able to get in correct your pitch quickly, otherwise the musicality of the solo/lick will be lost.
A good exercise is to start on a fret and work your way up the neck, bending up a whole tone as you go.
Remember, its the basics that keep the foundations rigid in your playing. You might be able to play a million notes a second, but if you cant hit that right pitch, you won't get asked back next week for the gig.
A bending lick example
E-12--------------------------------------15~~----
B-----15-12----------------15^(17)-12-------------
G--------------14^(16)-12-------------------------
D-------------------------------------------------
A-------------------------------------------------
E-------------------------------------------------
