Yes older, more experienced and knowledgeable suspension engineers like Herb Adams do know their stuff. They've been there and done that, as the saying goes.
Herb Adams didn't win races on theories but on documented facts. He's a chassis expert.
From his book, "Chassis Engineering" on lowering a vehicle, page 33 -
http://books.google.com/books?id=rY2ujnNrhf0C&pg=PA34&lpg=PA34&dq=Herb+Adams,+cutting+springs&source=bl&ots=HfQBfazM8t&sig=GOq_8E9aY8bQcQvQs2E7pOUryXw&hl=en&sa=X&ei=C7qvUsDaFYTtkQfjjYDYBA&ved=0CDMQ6AEwAQ#v=onepage&q=Herb%20Adams%2C%20cutting%20springs&f=false
"Lowering - Before you invest in springs to lower your car, you should be aware that your chances of success are much better if you simply cut your existing springs. All springs take a certain amount of permanent set after they are installed. (Note that new cars sitting in a showroom are higher than the same models with only a few thousand miles on them). This change in ride height is caused by the inevitable loss in load that any new spring experiences. If you put new springs on your car, they will settle as much as an inch in the first few months. Obviously, if your car was the correct height when you installed the new springs, it will be too low after a few months.
This is why I recommend you cut your existing springs and save the cost of new springs. The results will almost certainly be better. Your car's existing springs have already taken a permanent set, so you know where they will end up. If you want to lower your car, you can cut your existing springs to achieve the ride height you want with one operation.
Springs don't wear out, so you can save the cost of new springs if you trim your existing ones. We have found that most coil springs should be cut 1/2 coil to lower the car and still keep adequate ride height. If your springs have sagged, you don't even have to cut them because the car is already at a lower ride height".
Then on page 35 there are step by step instructions on how to correctly cut coil springs.
On variable rate springs, page 31 - "Variable Rate Springs - A study of the optimum springs rates for a car eventually come to the conclusion that the best spring rate is a variable one. We would like to have a soft spring rate to absorb the road irregularities and then have a high spring rate to absorb the larger bumps. Springs are available that are made with a variable rate. You can identify these coil springs by noticing that the spacing between the coils is different from one to the other. The design concept of these springs is correct, but in practice they don't work too well. Since car springs only operate in a limited percentage of their travel, the amount of change in rate is usually pretty small. Jounce bumpers provide this same variable rate feature with more consistency".
-- B.F.Goodrich T/A Certified Tire Specialist.