If I am correct (and I am not at all certain that I am), bank bonds are treated as high quality reserves for making new loans. (early-retirement-planning-insights.com)
Arguably Wenger isn't using him at all so maybe it would be better to let him leave to free up squad space, but realistically he is such a high quality reserve if both parties are happy with that situation then selling him for # 5m is kind of pointless! (justarsenal.com)
With this in mind Wenger has to start carrying quality reserves and rotating, not watching the pennies and pleasing the boss. (justarsenal.com)