Originally posted by photoptimist
First, it assumes that the only reason for a slow shutter speed is to compensate for low light. There's a very nice niche of photography that intentionally uses slower shutter speeds to blur moving objects in a scene whilst keeping the background or other elements sharp. Subjects such as water, sports, street, and fireworks can benefit from shutter times slower than 1/30 second (and with practice & SR, one can get good handheld shots at 1 second on a 28 mm).
Second, it assumes one never takes pictures at night or in dimly-lit cathedrals. Some conditions require BOTH higher ISO and slower shutter speeds.
Third, the two features absolutely do not conflict (the acceleration unit never prevents the use of SR and vice versa). At worst, they could be said to provide overlapping functionality in medium-dim lighting such as twilight. But in those conditions, the two features give the photographer more options to pick the combination of shutter speed, aperture, and ISO they need to make the image they want.
First. It's the basis of reasoning of using SR in GR. SR doesn't works effective at wide-angle. It's your pure fantasy about 1 sec SR effectiveness.
What is 1 sec effectiveness of SR in Pentax cameras? 3%? Not above.
Don't I never use SR with my cameras and have no experience with SR with all my lenses?
It's really good for FA77 or DFA100 and I can get till 3-4 stops sometimes. Very rare even 5 stops.
As for FA*24 - SR in K-5IIs or K200D can't even give me 1.5 stop in real condition with effectiveness at least 30%.
Sharp photo with FA*24/2 at 1/15-1/20 with SR - the probability is very low. The best case - 1/30 instead of 1/40.
I can say that Pentax's SR effectiveness at wide angle is 1 stop. The shooting with exposure 1/20-1/8 is the big lottery. With very low effectiveness.
Second. The cathedrals needs much wider lens than 28 mm equiv.
Third - see the point 1.
It's simpler and much more effective - to raise ISO than to use SR in GR. SR is weak crutch for GR. Not the same as for DSLR.
SR in small camera adds more weight, size and complicates the circuitry engineering of GRIII.
I had been using GXR with 18/2.5 for many years. I know that I say.