Thank you for your timely and meaningful post. Yes I agree that making enlarged negatives with materials already on hand is a viable alternative to the digital route. I have done the process using conventional panchromatic 100 ISO film as an interpositive and then enlarging that interpositive onto lithographic film. Lith film is very inexpensive. Freestyle and Photo Warehouse both handle lith film in various sizes. Some of them quite large.
The method that I described is certainly inexpensive since it involves conventional film only in the interpositive stage. Since it is contact printed with the original camera negative at the interpositive stage the cost of materials is certainly minimal. The wonderful thing about lith film is that it doesn't exhibit grain in the same manner as conventional pan film.
You are correct, David, in the amount of control one has in this process or in the process that you described using paper interpositives. I don't know that enlarged negatives have more control then digital. However I have not encountered a situation that I did not have sufficient control to accomplish the task that I wanted to accomplish.
The benefit for me is the same benefit that I experience throughout all of my wet darkroom experience. That is that I am doing something that involves direct physical involvement to produce an image aligned with my desired objective.
For those interested in doing any of the methods described, there are excellent resources on Ed Buffaloes site www.unblinkingeye.com
I believe the author of the article that I am thinking was Mr. Bob Herbst. Examples are shown of Mr. Herbst's results using the method using lith film. Also I believe that there is another article that describes a direct negative to negative process.
I have also found resources by doing a google search on platinum printing. There are a couple of photographers that use enlarged negatives and the last that I checked they were freely sharing their procedures with us. I'm sorry but their names escape me at the moment.
Once again, David, thank you.Good luck to any and all that choose this means of expression.