Wrong - that's just a myth. Failure to display your tax disc is a separate offence to not actually having paid for the tax. Even if you have a disc it is an offence not to have it in your window.
http://www.penaltychargesforum.co.uk/sh ... isplay-tax
From dvla's website
I have not received the tax disc. Can I use the vehicle without the tax disc displayed?
When you apply for a tax disc online or by using our phone service you are able to legally continue to drive your vehicle for up to 5 days after the tax disc has expired while you wait for the new tax disc to arrive. This will only apply when you have applied for a new tax disc before the current one expires. You should continue to display the expired disc on your vehicle, until the new one arrives.
So dont know really with where i stand taxing whilst the car was sorned? Thats the point i was making i tried to apply before the 1st so i could have my disc in time but they would not give me the option when to start the licence from, it was obvious i did not want it from the 1st March.