chain useage is a really difficult topic to keep operators up to speed with at a Brigade level. There are so many issues that relate to their use, that, by default, most RCR crews go with what they know better and just make do.
The use of chains in lifting the steering wheel and column is from a slightly older time, when the steering column was all one relatively straight tube, and so it pivoted nicely and lifted comfortably. These days, modern car construction has a lot more universal type joints and bends and a lot less rigidity, and therefore it may not lift as easily and just bend and be a pain in the bum. Thats why the newer techniques of dash lifting and rolling work even better, in that the newer assemblies are an integral part of the dash, so not only are u lifting them, you are making more space everywhere.
The other issue with chains is that their effect is not always predictable, or controllable. They can tear the structures they are pulling, and may not impart an even pull, which can result in sudden loading (or unloading) which can effect the stability, or safety in the area around your trapped person.
I know of at least a couple of people that are keen to introduce frontal zone separation for head on impacts using chains. Put simply, you reverse the force of impact, with a chain set, winch and a big arse anchor, and effectively pull out the front after a few relief cuts. It is used in a few overseas countries, some rave about it, some are skeptical about it, my reading of the research is that the jury is out on its cost effectiveness and safety concerns (I'm sure one of the proponents will agree to disagree with me, we've certainly had a discussion or two about it). Either way, it's a good topic for a discussion about vehicle structure, construction and impact force vectors.
Lastly, like many things that aren't rake hoes or knapsacks, the CFS has its head up its arse , sorry i mean in the sand, in regards to chain sets. They have no planned maintenance schedule, no guidelines for inspection or serviceability checks or life of type info that they will sign off on. If you have a set, I doubt you would get them replaced (happy to be corrected here).
They have many many uses other than lifting steering columns, and should form part of a General/Heavy Rescue stowage......but thats right, bugga....we don't do them do we