Hey Tonks - the exciting things you do these days, eh mate?
Just about to dash off overseas again, but before I go, a quickie explanation of the effect upon transition point of the adverse pressure gradient:
Remember that Bernie Ooli tells us that, (blah blah inviscid, incompressible flow, low speed aerodynamics blah blah, etc...) for all intents and purposes the sum of static and dynamic pressure will be constant? Well, aft of the point of maximum thickness on a aerofoil, the airflow begins to decelerate in the direction of flow. Thus the dynamic pressure reduces and hence the local static pressure begins to increase (Thanks Bernie!) - if the static pressure is increasing in the direction of flow (and AP3456 unfortunately forgot to include the word 'static' in the text here), then it has been found to be a physical impossibility for flow to remain laminar - it just can't. Not even for the RAF!! Where you have increasing static pressure in the direction of flow, you have what is termed an adverse pressure gradient - the greater the rate of increase of static pressure in the direction of flow, the earlier the transition from laminar to turbulent flow with its corresponding increase in drag. Hence the transition occurs very close to the point of maximum thickness of the aerofoil.
Have you found out why minimum power speed and minimum drag speed are related by a factor of 1.32 yet? Not many people will be able to explain that one to you......