Most of the big discounts are coming hand-in-hand with a large optional spec list. Seems like VW dealers have far more leeway to give discount on additionally specced cars.
For a vanilla order you might not realise big discounts, or your p/x value may suffer as a result. I've only saved £800 on my GTD on paper (with freebies), but by the time I get mine, the overly generous fixed p/x arranged at the end of March means that at time of order completion i'll get £1700 more p/x than I would've otherwise expected (£1700 more than Glass' say it's worth) - thats a "fair" £2500 discount as far as i'm concerned. Cost to change is my biggest concern - i've had poor p/x prices and broker discounts before, they usually rob Peter to pay Paul. Gotta be aware of what's right for both ends of the deal.