Driving up his transfer value? Seriously? The club would, most probably, give him for free. The issue here is not about selling him. The issue here is to get rid of his outrageous salary which is weighting on us.
There is no doubt that if played against nobodies, Bastian can still score a great goal or pass the ball. If you play Scholes or Pirlo you'll probably notice that they still have it and would do well in a game like this which was at par to a testimonial game. The issue here is whether he can still run, harass players and play like a 200k a week player. We all know the answer to that