Spotlight
Thanks - and I think you've clarified what I was trying to say - but I having read the AIP I was barking up the wrong tree anyway.
The conflicting statement that straight in approaches must give way to circuit traffic is, I think, designed to prevent a conflicting straight in on the opposite runway - i.e a straight in must give way to all other traffic so theoretically could go in if the only circuit traffic had just turned crosswind but in practice can't really. ENR-64.6 prohibits the scenario you proposed pretty comprehensively.
Having re-read AIP ENR64.6.4 however, there is no point at which you get automatic priorty on a straight-in and at all times you must not get in the way of aircraft on base or final.
QNH1013 - it seems that you're correct - and relying on the airmanship of others makes me nervous!
UTR.