Giving him that contract was pretty stupid, but it's not the end of the world everyone thinks it is.
A good, in contract player like that, at the time would of cost around 50m. And say he'd be on 200k a week.
So, if he was on 500k a week, then he's cost us 15.6m a year "fee" (300k*52), so over the 2 years it's around 30m (not taking in to account the -25% for not being in the CL, and the fact he was loaned out).
If he actually played well, then he pays for himself, or there is a chance we can move him on and get some kind of fee.
The issue is, he didn't play well, and had he been loaned out and also not played well and there were no takers, we'd have been in real trouble - and also what happens if he did alright and it was time to renew - it's not like we can give him LESS money.
It was a stupid not thought out decision, but luckily, in hindsight compared to a normal transfer who might have got injured or flopped - it's not really cost us more than that. But also because of the high wages, it also pumped up several other of our players wages, which is bad.
We should of instead given him a signing on bonus, and a normal wage. (But then that's of course more initial outlay)