Also, if you think something is important, but the form doesn't make allowances for you to write that then say so and make a point of writing it in the additional information section. Read the guidance notes too, theres sections on the form that ask you how far you can walk ect, but remember that they want to know how far you can walk without pain or discomfort - so if you can walk 100m but after 20m you are in pain, say 20m - it's like a puzzle sometimes filling those forms in!
The DWP are being very strict at the moment, something about the company gets payed more if they 'correctly decline' a certain number of applications, so that decison makers are not inclined to accept applications that they shouldn't... But it has caused a few people who should be entitled to DLA to be declined. If you don't get what you think you should get and what the decision makers say you should then ask for it to be looked at again and a lot of the time it will go in your favour.