Yes, but if you put aside all of the variables, and lock in to a two year deal, then you know what your budget is for your fuel costs for the next two years and you can forget about it.
We all think differently but, personally, I've got better things to do than spend time worrying about whether I'm paying a little more or less than I could be. Then again, that's probably because I might not be around in two years
Except there is a 50-50 chance you'll pay more by actively choosing to do something (like lock into a 2 year fix) than by sitting on your arris and doing nothing (variable rate).
And now it seems that even if you do chose to fix, and the price goes up there is a 50-50 chance the supplier will go bust and you'll end up on variable rate anyway.
Heads they win, tails you loose. The illusion of choice only exists if you can trust the suppliers to deliver what you sign up for.
So my decision is based around the premis that Boris won't allow (too many) grannies to freeze to death this winter, and most grannies are on variable rate.