those in between sounds are actually something special to a strat, gives a glassy, twangy sound. I think U2, John Mayer uses alot of bridge+middle

If you read up the strat history, you can see that they were initially produced with only a switch for 3 positions, but musicians eventually found out that they could have another sound by putting the switch in between positions 1-2 and 2-3.

Try using less distortion and try using overdrive instead when using those positions. Or try to play clean with the gain slightly up, or with a louder volume. Then you can really hear the qualities of these in between sounds.