Good... in principle. Although we have to hope that the CMA proves to have some actual teeth unlike the rather feeble Ofgem and that it doesn't conclude that everything is fine.

Yep, the size of the investigation is meaningless, unless they can do more than tut at them the say "naughty boys".

If they are honest and thorough, all they will discover is that the industry is too opaque for collusion and price fixing to be found. If they want to fix it the same approach as that used in every other case is required, which is either to force all trades Including those between arms of the same corporation) to be placed through a public exchange, enabling regulators to use software to spot price fixing, or else to tighten up accounting rules so that auditors must sign off on the books and balance sheets of the units that dig up the gas, those that transport it, and those that sell it as separate entities.

In other words, boring, honest, technocratic stuff that won't impress the howling hoards or the Guardian - if those are still in any way different things.