First bad batch, plan to fix it

Okay, I could use your input here. I've been making wine from grape concentrate from the grocery store with great success -- up until my last batch that I bottled recently.

I cracked open a bottle, and it was kind of watered down. It didn't have the full compliment of fruity goodness and alcohol punch that other batches have always had. I think I did something like use too much water in the simple syrup that I made and added to the carboy before bottling. I guess I got distracted.

This is my proposed fix: I plan on decanting two thirds of the bottles in this five-gallon batch and blending it with the next five-gallon carboy of the same stuff. This time, when I backsweeten, I plan on sweetening the remaining third of the old wine rather than making a syrup with water using the same amount of sugar I always use. Hopefully this will make the resulting wine pretty much what I've always come to expect.

I've stabilized the new batch already, so I think I'm okay with the camden for this double batch even though I'm exposing the old batch to plenty of air. Wine is pretty forgiving, I figure.

Your input would be greatly appreciated.

doesn't sound like too bad of a plan. In the future, use some of your wine to backsweeten with instead of simple syrup. The simple syrup will dilute your wine down some and if you are using frozen concentrates up the about to 4 cans per gallon if you haven't done that now.