magpienja.
There's no reason at all why you can't fly the LLR in the way you state. The part of the LLR rules you quote are designed to stop people from, let's say, orbiting over their house or similar. As you can imagine, this would be quite hazardous to other aircraft transiting the route in a restricted piece of airspace both laterally and vertically. Your pilot friend has probably flown up and down the LLR many times but if you'd like to see some more detail about the route you'll find it here....
http://www.caa.co.uk/docs/299/DAP_ACD_ManLowLev.pdf
Spiney