Include

[130CC]

Just my two cents but...
In regard to length vs width the physics of it remains the same in regards to weight on area. If you increace a tyre patten forwards lengthening the tred by 10% then the load per square foot is decrerased if you get my meening. The same applies when you go in width. Here in Canberra your rego is based on the weight and class of your vehicle. A 980kg suzuki swift costs about $500 for the year while the 130 costs me $980. What they don't take in to account is that the 980kg's is spread over 1/3 the size of the road surface area/contact in comparision to the tyre on road contact area of the 130 you do the maths pounds of preasure per square inch of contact is the same(roughly) I am just equivalent to 3 suzuki swifts. If they ever figured this out I would be paying more for rego, thank god they haven't worked it out or maybe they have their just being nice(government run so I doubt it). Sorry bit of the topic but helps in explaining.
When in sand you have now take in to account the forward roll of the vehicle when changing gears the wider the tyre is the faster the car will slow down on gear change because more forward contact (front face size) of the tyre building up as you slow down. Then you have to take into account the cut of the tyre the widder the tyre the more it tends to not dig in to the sand as you drive because of this wider face, the longer the tyre the more it tends cut in to the sand increasing the size of the face of the tyre. You might start to get where I am going both tyres whether the increase forward in length or increase in width the performance is about the same some people will swear by fatties and some about skinnies but it is all about increasing the footprint of the vehicle to place the vehicles weight over a larger area therefor increasing flotation of the vehicle on the sand.
I have both fatties and skinnies and prefer the fatties as the surface area at low preasure apears to be bigger than that of my skinnies.
Adam