In my opinion modern hinges are a minefield and are not truly peelable the way vintage hinges are. I agree that it is possible to use very small amounts of moisture to minimize the potential for damage to the stamp/album page but when I buy hinged collections, I set the price I am willing to pay is based upon how it is hinged. Beware those collections that require you to soak the entire page just to safely get the stamps off of them, typically they are not worth the time it takes to remove the stamps. You can still buy vintage Dennison hinges and some folks will cut them in half to save money.
Split back mounts can damage mint stamps by leaving a mark in the gum. This typically occurs if the album is stored improperly; facedown and flat instead of standing up and/or is compressed tightly among other albums or in a slipcase.
Many prefer top loading mounts but improper handling or mounting these can also result in stamps moving or even 'getting away'. I doubt that this is a significant issue with a collector who understand how to handle an album but keep in mind that our albums often end up in the hands of the inexperienced. Don
Hinges new and old leave marks on gum. Stamps are exposed on pages so subject to damage. Split backs MAY leave a mark on gum but data is very anecdotal (not nearly 100%). Top Loaders do not leave marks on gum but less secure the split backs but damage is anecdotal.
If one is going to use a hinge and get the gum disturbance, then a split back should offer no additional gum risk but better protects the stamp overall.
In my experience, the stamp damage resulting from split-back mounts flows from the carelessness of the user. Too many people stick down both halves of the mount. And too many sloppily apply saliva or glue to the mount so that it damages the stamp by leaking through the gap and sticking the stamp to the mount.
I agree that the risks outlined above are 'user error' based.
I tend to comment in the context of posting on a public forum that is read by many folks. My intent is to prevent 'user error' via better informed people; by making folks aware of the potential issues and risk hopefully they will better be able to avoid the pitfalls.
I think that sometimes others read posts and think 'hey, I have used this for years and have not had an issue'. That is not the context of my posts nor would I challenge their experiences. I think that our hobby can always benefit from multiple points of view but I also think that it serves a good community purpose to note the potential hazards. Don