No, it does not. Say I'm 6' tall. "Normal" BMI is between 18.5 and 25, which translates to between 136.4 lbs - 184.3 lbs. Telling me my weight is going up or down tells me nothing about whether I fall into this healthy range. And, depending where I fall (below, within, or above the range), the actions I would wish to take differ. It's that simple.

What instrument do you have that measures your "weight relative to others and your history"? Don't you only want to measure it relative to other healthy individuals? And, if you are particularly underweight or overweight, wouldn't you want to know when you're in the normal range? An instrument that only tells you what direction the change is doesn't tell you any of that.