Yards Per Point Question

[Sandinhand]

YARDS PER POINT
TEAM OFF DEF DIFF
SD.ST 11.5 14.5 -3.0
BOISE 13.4 22.8 -9.4

My simple questons is, how to to understand, SHOULD I use this as part of my handicapping, the math calculation. I see that SD ST has a better offense and Boise has a significantly better defence,...thus the number in the sum of the difference, -6.3
Am I to understand that in theory, Boise should be favored by 6.5 ?
What would be a near perfect number or what is an excellent number ? In other words, is there a standard 'perfect' number to reference too ? Thanks in advance

[statictheory]

I thought i answered this, maybe it was another thread.
figure yards per point for both teams divide the yards per point into the average yards allowed by the opposing team. do this for both teams and you have a basic score. add more details and stir