Sorry, but this is just not true, regardless of who said it.
The points are scored according to the following descriptors:
a. Can stand and then move more than 209 metres, either aided or unaided. 0 points
b. Can stand and then move more than 50 metres but no more than 200 metres, either aided or unaided 4 points
c. Can stand and then move unaided more than 20 metres but no more than 50 metres 8 points
d. Can stand and then move, using an aid or appliance more than 20 metres, but no more than 50 metres 10 points
e. Can stand and then move more than 1 metre but no more than 20 metres, either aided or unaided 12 points
f. Cannot, either aided or unaided. 12 points
(i) stand; or
(ii) move more than one metre
With all of these activities, it’s all about performing each activity safely, to an acceptable standard, repeatedly and within a reasonable time period. (There is more detail about each of these things but this is a précis.)
Using a wheelchair to do any of these is not expected ie, any movement you can only manage using a wheelchair is ignored.
To qualify for the standard rate you need to score 8 points. For the enhanced rate, 12 points. To qualify for a motability vehicle (of whatever kind) you need to be entitled to the enhanced rate.
This information I have just copied from the new edition of the Welfare Benefits and Tax Credits Handbook 2016/17
For any more information or assistance, look at Personal Independence Payment - Citizens Advice or http://www.benefitsandwork.co.uk/
Sue