Using the find tool on the PDF discovers that the word “can” is used twice, while the word cannot is used three times. I find that significant 
Not wishing to claim the clever person medal I do think I have found the driver regulations that Rog and his team of URTU representatives use.
Drivers’ hours rules: the basics
From this information I gleaned this paragraph;
Drivers must normally take at least 11 consecutive hours of daily rest. This can be reduced by up to two hours on no more than three occasions between any two weekly rest periods.
This guide developed with:

During my research I also came across this from the boss.
Thursday 08 February 2007
URTU regional officer Mike Billingham says the new drivers hours’ rules could mean drivers are pushed to their maximum working limit so companies can avoid recruiting more staff. Billingham says that companies working on supermarket contracts “don’t want to” pay extra for more drivers or temporary agency staff.
The changes under the new rules effective from April 11 state that a driver must show two weekly rests, one of least 45 hours, in a rolling two week period. The other rest can be reduced down to 24 hours if time is made up by the third following week.
Billingham says employers will stick rigidly to a 24-hour rest period for one weekend and 45 hours for the next which means that many drivers will only have a day off in nearly two weeks. “I’m not sure that will do a lot for road safety,” he says.
I feel the URTU could almost be accused of scaremongering to boost their membership, not mentioning that the horse escaped in April 2005 when the Unions could really have made a difference by standing up to the ridiculous RTD and Periods of Availability, especially for the drivers who are not paid for them. But that is for a new thread.
I honestly think this particular thread is at an end, the regulations allow for flexibility on both sides and that is how it should be. A company can ask a driver to reduce his rest, they may even plan him like that as it is their right, the driver may refuse but if he does it too often he could be joining Rog and myself in the big house for our wages. 