IMHO, while Superman could normally lift things far heavier than 100 x his own weight, if it's a Krypton-specific-level grav field, his physiology is keyed to depower physically just as the specific radiation signature of Krypton's red sun depowers his solar-based powers.
I think that Superman deriving powers from only certain values of G force is goofier than deriving powers for certain colors of sunlight. At least with the red sun, we visually see what's going on, so it works in a comic book.
I much prefer the notion that there's multiple sources for his abilities (gravity for a little bit, yellow sun for the bulk), so you don't have the dorky "red sun flashlight", which struck me as way way too easy. Why bother with Kryptonite when you can retrofit a tanning booth? Heck, I'd prefer the notion that the red sun stuff is nonsense, that the Sun Thrivers live in every red sun and they're the ones sapping Kryptonian powers.
Kurt, do you think that people who obsess about Superman's powers and how they work are weird? On a related note, do you have Mark Waid's phone number?
We aren't supposed to 'see' his X-ray vision or heat vision beams but comics do portray those for us to 'see'. We're not supposed to 'see' the magnetism of Cosmic Boy or Magneto but artistic license shows us those in pics that would be truly invisible to the characters in the fictional worlds. Showing a grav effect is exactly along the same artistic license lines.
Superman: Last Son of Earth, while an Elseworlds, clearly is another take on the Byrned era of Superman. That is obviously Byrned Krypton and it has a high gravity. Clark/Kal on Earth operates at Action Comics #1 levels due to his adaptation to Krypton's environment. So, yes, the books do have some support for the AC #1 position.
OTOH, many Pre Crisis tales show Superman's powers being halved or otherwise curtailed by high-G attacks, esp. those duplicating or exceeding Krypton's gravity. It does seem based on the books the K-gravity was a magical number the way things are portrayed.
It must be noted in the real world that some things have specific values where an effect is triggered. Green chlorophyll, the most abundant kind and primary pigment in photosynthesis, specifically is keyed to red light so any other kind of light doesn't activate it. Some kinds of salamander can be triggered to change form at certain temperatures but remain essentially fishlike at others. A certain pH level is needed for some creatures to live and others live in another pH range. Current research on immunology shows microgravity suppresses the immune system due to subtle changes in cellular cytoskeletal organization; this could easily be extended to how a specific grav level or range would activate or deactivate Kryptonian physique powers.
What was it the First Doctor (Doctor Who) said? "There's always a way."
It helps to have a wide and deep understanding of the real world. As Mister T said, "Stay in school!"
Oh, and before I start slinging any 'scientific lightweight' insults (I have been remarkably forgiving on this matter while others have freely insulted those with my mindset on this, btw) around, let me quote what I said before on scientific extrapolation.l
Yes, let's forget all the brilliant stories from the S.F. greats like Fox and Hamilton that did indeed examine the scientific implications of comics super-heroes. Let's toss out Flash's aura, vibrating through walls, super-speed time travel, vibrating to invisibility, and Superman's heat vision 'cause they 'just don't make sense'. Those are examples of brilliant scientific extrapolations from what the powers are about and could possibly do.
I agree with JulianPerez that scientific extrapolation in comics for its own sake is somewhat sterile and useless. It must be coupled with adding value to the stories (which the above examples abundantly do).
But to disregard scientific extrapolation altogether is sliding much too far into the other extreme. As abundantly proven by these examples -- which I've posted ad nauseaum -- the great Silver Age writers and the legendary editor, Julius Schwartz, all subscribed to this kind of thinking. This is, afterall, a site devoted to celebrating the Silver Age. To denigrate this aspect of it is not in keeping with that spirit.