Didn't Ernie Gutierrez make a tube style case? I'm pretty sure the Glenn Collection has one.
Yes. The Gina cases actually predated the Fellini and it's a pretty sure bet that the Fellini was directly influenced by the Gina cases. One member here on AZ has access to many unfinished Gina case parts if I am not mistaken.
The Gina case was built internally similar to the Harvey Martin with very thin nylon separating the cue parts. Externally the case was made with the leather glued to the body and the ends folded over the top.
Harvey Martin isn't really well known but if you really want to give credit where credit is due then the credit for the hand-finished ends should go to Martin. I don't know if Harvey Martin actually made the cases or not. But I can't find any examples of this technique on other leather goods. The obvious comparison would be upholstery except that upholstery hides the ends of the material so that it can be tacked or stapled after being pulled tightly.
Laying the leather up over the ends and finishing it with a patch of leather seems to be fairly unique to cue cases.
It cannot be understated how hard this is to do and get right. Very very easy to get wrong. You will find no tutorials anywhere (at least I never found any) on how to do this technique. In upholstery you don't have to be super careful about how the leather fits together because it's tucked away and unseen. So upholsters have all sorts of tricks to make the leather behave and look great for the part you see.
I would like to add that there ARE examples of upholstered cases where the ends are tucked into the tube and then leather/vinyl covered cap is placed in the top. This is NOT the same as the hand-finished ends I am speaking of.
In a case like the Harvey Martin, Gina, Fellini and GTF the person doing the work doesn't have a lot of room for error because what you see is what you get.
Harvey Martin and Gina both skived the leather to almost paper thin which certainly made the job much easier. The drawback to this is that it decreased the durability of the leather tremendously. This is probably a reason why so few of these cases have survived. A lot of them were probably thrown away as junk when the leather wore through. For this reason surviving examples should be prized.
Fellini used thicker leather on the ends and this came with it's own set of problems. Namely keeping the leather down. You can see on a lot of Fellinis that the ends are separating from the body. This happens when the leather and glue react to climate change. Sam Engles also had this problem on many of his cases. And this is normal because without a Martin or Gina to study then those that follow only have the examples available to them.
We have invented a way to pretty much insure that the ends stay put forever for the GTF cases. So far 3 years and counting it seems to be working.
But yeah, the real credit goes to Martin for the hand-finished ends and then to Gina for the flush slip cover case.
To be fair slip cover cases have been made for centuries. But as far as I can tell the modern version using nested extrusion tubes started with Ernie at Gina.
Note: There may be examples of the flush-lid slip cover style as Viking Cases which were also from the 60s.
(I don't have any examples of the Gina - Maybe someone else could provide some?)
Martin:
Fellini:
Engles:
GTF: