I do have some fans running.
I was thinking in terms of pressurizing the living area with
one fan blowing fresh air in, and the rest of the place closed up. The slight excess pressure (even 0.1 in H20) will trickle through to the crawl space through all the inevitable little openings (piping, electrical conduit passages, etc) into the crawl space and force the decomposition gases back outside through all the inevitable openings from the crawl space to the outside.
Practicality depends on the weather. You don't even need a very big fan.
Effectiveness depends on a couple of things, notably how much of the smell has infused itself into the living area high-surface area things like carpeting, furniture, etc.
You should start out with a large fan running full blast for a while with another window open to vent the pressure so that you are purging the place. Then, when the large body of stinky air has been replaced go to the small fan and
closed windows to keep the place pressurized just enough to kerp more stinky air from coming up from the crawl space.
Terry, 230RN