Some points to keep in mind...
1. Doubles is the great equalizer. I have seen poor singles players be very good doubles players.
2. It is harder than you think to break the weak player's serve. That strong player at the net can create problems. I agree with an earler poster that sometimes the stronger player can be broken because of errors from the weaker partner.
3. Hitting to the weaker player is a good strategy when they are both at the net or both on the baseline. However, don't stop hitting the right shot for the situation just because it is to the strong player. For example, I play mixed doubles with my wife and in a tournament lots of teams have the strategy of playing to the woman. This backfires on them because they become predictable and I can effectively take 2/3's of the court away from them. Unless they go to me or behind me, I just keep getting more and more aggresive at the net. My wife is pretty steady and a typical point when she is returning serve will be...backhand return, backhand, backhand, volley winner by me.
4. When in doubt, hit it down the middle.
PS 6.0 95
M: Klip Legend 16, 53lbs.
X: Gosen OG SM 16, 51lbs.