Hi John, well I don’t have and have never played a J45 so I can’t offer a very good comparison, my 35 is smooth as silk, guess that’s why I have fallen in love with this thing. Now that being said, if the truss rod is properly adjusted, I have a .004 thousandths relief put in mine that’s past the seventh fret, and the frets are level, easy to check with a machinist straight edge, I see no reason it would be like that other than large fret wire OR to light gauge strings. On a short scale the string tension is reduced considerably and requires less downward pressure on the fretting fingers. If you combine to much pressure and light strings and short scale on a slide I can see this feeling being there.
On mine I use Martin 12/54’s phosphor bronze strings, on a ss you could even go up to a 13/56 and still be ok. This may elevate some of what you describe. But Always check the neck setup before any other adjustments or changes. It is absolutely amazing the difference a properly adjusted truss can make in all respects. My 35 was ok, but didn’t play as well as I like and the factory had the truss rod backed off all the way, a not uncommon practice with makers as they don’t know the climate the guitars are going to. Made in Bozeman the RH is most likely 10% here in Oregon on the coast it is 50 to 60% RH.
I have a set of tools that I keep to check my necks and make sure everything stays in sink.
This is my first Gibson so it is the only one I can judge by.
I will offer this, keep in mind I am no expert on playing that’s Ben’s dept., however, about a year ago I noticed that I was having finger pain sometimes and hand issues as I play anywhere from 3 to 6 hrs. a day, I read an article concerning the pressure being exerted on the strings and overworking the hands. I made a conscious effort to (“ease up”) and it takes a while, but it is not necessary to press hard against the frets, we have a tremendous amount of strength in our hands being exerted on the neck. The harder you press the harder you work, once a string is fretted no need to press any harder. It took me several months to change this behavior but for me at least it has paid off in ease of play, speed, and accuracy, and allows me to play much longer without fatigue.
Anyway out of this you may find something useful that will help. By the way going from the ss to a Martin which is 25.5 is a huge change so you need to adapt the feel, at least I do. Jerry