Orca,
Sorry I missed your question yesterday, but it seems to have been answered by the FOI post. I think the point is that it is, in my view, not that much in the big scheme of things. Compare that with cost of trying to do it with a number of Typhoons (and that's ignoring the incredible waste of front line assets) and it really has been a drop in the ocean.
To be honest, the bigger problem was (and I'm not having a dig here) that the team became dominated by Harrier pilots at a time when that force was getting a bit short - a relatively small force constantly tapped for pilots to go to RAFAT, CFS, etc. There was a lot of resistance to use more pilots from other forces; I was once told by one of the brethren that "If you start using Tornado pilots, you'll start having a lot of crashes."
We also had a bit of a dearth of Hawks elsewhere, but RAFAT was deemed such an important asset that the other Hawk fleets were always tapped for a replacement jet whenever needed - no matter how congested the training pipeline had become.
The one thing we could never measure was the effect on recruiting (not such a big deal at the moment) and (bigger) public image. No one can reasonably deny that the
PR effect is huge - interestingly for all three services, not just the RAF.
My point is that money wasn't really the kicker - probably isn't the be-all etc of the argument now. But the team was a sacred cow to the chiefs so was repeatedly preserved.
Have things changed so much? I wouldn't think so, but we live in strange times. If it all goes wrong, we can always start a "Decision to axe the Arrows was Bonkers" thread and keep feeding it for the next 10 years.