My advice is that one should never use a hair dryer as the
stream of heated air is too localised. I use a fan heater. But I have seen
Peter Frederick use a hair dryer without any difficulty.
I guess the gist of the discussion is how short is short and how long is
long, and how local is local. I must confess that I haven't made a gum print
in over ten years but I did teach a number of classes in the early 80's
using the substrate method. At times exposure and development was so short
we were using 2 dryers to halt the development and as I recall the time
between shiny wet and matt wet was 15 to 20 seconds. Full drying took maybe
1-2 minutes at most. it might be possible to dry in this time with a fan
heater, I dunno. I had tried different methods of drying earlier without
substrating with varying degrees of success, I'm sure I must have used a fan
heater but the memories a fog.
As for the muss and fuss of substrating. Once you have your pins mounted it
only takes a minute to drymount the paper and a minute to strip it off. Not
much more time than it takes to magic tape it down, etc.
Note also when substrated, you essentially only have one side of the paper
wet, I think this aids in the process.
Like they say, "Whatever works."
Dick Sullivan