Yeah, you have good info here:
basically these are the factors to think about, for body roll:
1) In that configuration, your shocks are effectively made softer.
Here's an example, that looks to be about a 45* angle. So, lets say you have roughly 18" vertical, 18" horizontal, that means the shock is 25.5" in length to go from point A to point B. Now, say you compress the suspension 1". Its now 17" vertical, 18" horizontal, the shock would now be 24.76".
So, for 1" of travel, you only compressed the shock 0.74". If you were able to get a true 1" of compression, you'd see a 35% increase in damping force alone, without any other change. Thats one big reason the /\ setup sucks. But, as noted, you can cheat, and use a shorter shock and get more axle travel.
This will also increase your straight up and down bump damping by the same amount, so it would be stiffer.
2) Now look at it from a statics/dynamics perspective (sorry, I'm an automotive engineer..). Think of the body like a teeter-totter, with the roll axis as the center fulcrum. You can choose where to apply the force of the shocks, and there were will be a lever effect. Apply it further out towards the wheels, it will have more lever effect, as the cost of needing more travel.
So, that there again multipies your body roll effect, but in ths case if they are moved further out, it won't really affect the up and down damping as much, just the lean.
Ultimately, you have to make the choice based on how much shock you can fit. The further out you go, the more length you need for flex travel, but the better roll control you will have.
If you want max damping for up/down bump travel, then mount them perfectly vertical.
If you want max roll control damping, then mount them on angle so the shock's travel direction is in line with the travel of the shock mount on the axle. (i.e. in a roll/flex situation it does move up and inward, so you do want some inward tilt, just not anything like in the pic...)