I'm totally with Gregore - adding more pressure is NOT the key to removing whey. Pressure is needed only to persuade the curds to bind together (get a good knit) - and if you force this to happen too soon, as Gregore says, you will trap whey inside the rind.
Consider that a parmesan needs very little pressure to get a good knit, even though this is one of the driest of all types of cheese. It knits together easily because it is pressed while still very warm and relatively high pH (6.2 or so). Cheddar, by contrast, is pressed after it has reached a low pH (5.3 or so) and has been salted, making it much harder to get a good knit -- but this does not mean you should crank it up from the start; quite the contrary. With cheddar, you have already stabilized the pH by adding the salt, so you've got plenty of time to achieve the knit. Work your way up gradually, allowing the whey to trickle out steadily over a longer period of time.
To get a drier cheese, decrease the flocc time (time of setting after adding rennet); cut the curds smaller; stir more/longer; cook more (higher heat - within the limits of what the bacteria you are using can tolerate).
Note that gooey texture is also a function of pH. When pH drops below a certain level, the proteins release moisture; when the pH raises above a certain level, the proteins absorb moisture. This is how a "bloomy" cheese works - you allow the pH to drop very low (4.5-4.7), which in turn drains off some of the calcium (which otherwise would contribute to a more crumbly texture); then you allow mold to grow on it, which works on the cheese to raise the pH back up. If you try a bloomy too soon, even if it is covered with mold, you are likely to find the inside to be "chalky" in texture - the pH hasn't risen high enough yet. But when the mold has worked long enough, magic happens inside - the chalky texture transforms into a gooey delight as the proteins reabsorb moisture.
Whether any of that has anything to do with your experience, I don't know ... probably not, unless you had a good infestation of PC on the outside. But it does make me wonder if by any chance you never got the pH of the cheddar down below the threshold where the proteins hold onto moisture ... ?