"Ace Pilot" wrote in message =
But I was curious to know if there are pilots that take full advantage
of this distinction. Does anyone actually make use of the Class E/G
boundaries depicted on sectionals? If so, how? I suspect the most
common use is doing T&Gs in the pattern below 700 feet AGL when the
weather is marginal. Other uses?

Those circles aren't to keep VFR pilots safe when the weather is marginal.
They are to lower the floor of controlled airspace for the benefit of IFR
pilots.

This accomplishes two things:
1. Allows ATC to provide control to lower altitudes, primarily
separation from other IFR aircraft.
2. Makes sure any there is sufficient visibility / cloud clearance
for visual separation techniques to be used between any
VFR aircraft that might be present.