For what it's worth, and I've said this a fair few times to people on here in other mediums, I personally think Doherty has reached his ceiling. I hated him as a player, a lazy, overweight full back who wanted to attack and couldn't be bothered to try and defend, and was absolutely astounded at how Nuno turned him round to be a very important part of the team who contributed to two very successful seasons. But this season it was noticeable just how much space he wasn't getting, last season he would ghost into gaping areas and have oodles of time to control the long ball and decide what he wanted to do, it was extremely effective. This season though teams seem to have got savvy to it and while Doherty still pushed forward he didn't have the freedom to work in that he had last season. I think this is why he lost the ball a lot more as he was pressured much, much quicker. Yes he still contributed and I think he may have cut inside more this season than last (could be wrong there, I have form), but towards the end he started to look very ineffective (admittedly he wasn't alone).
Does he have it in him to change his game and give opponents something else to think about? I don't think so. Maybe he does, he's proved me very wrong once, but I doubt it. This limits our tactical options quite severely. Soon to be 29 and with no room to grow I think £15m plus add-ons (or whatever it is) is about right. Do I think it's wise to sell Doherty for that price and not replace him? No. Do I think it's wise to sell Doherty at that price and bring someone in who can play in different ways / is younger with a higher ceiling / has more to their game? Yes. None of this has happened yet so I can't say how it will pan out but yes I do have trust in Nuno, Jeff and the club as a whole, so if we go into October and the window slams shut and we're markedly weaker than when we finished against Sevilla then I will criticise, until then I'll leave it to the professionals to run the club and identify players who can push us on. That's their job, not mine.
So if everything turns out right then no, we're not "giving him away". Even if it doesn't then £15m is not "giving him away".