How dry is "dry"? I was refering to the carpet/pad being at a state where it was more moist than the surrounding air, not squishy wet. You're right, that goes away quickly if your vac is powerful enough to pull it out. You probably used a truck, right?
Unfortunately, measuring it is somewhat technical and requires equipment few people have.
If you place a paper towel on the carpet and stand on it for 30-60 seconds, it should not feel damp. That's dry carpet.
In some climates, getting carpets dry quickly enough is fairly easy. In others, it's very hard.
Without a truck-mount, airmovers, possibly dehumidifiers and expertise, it can be dang near impossible.