I was wading boot tester. I may be wrong but I guess your hip boots had a one piece felt sole like on this pair of Simms. Am I right?
If you have a higher quality boot like this Weinbrenner Borger Boot that has a "stacked" heel made of separate stacked, glued and sewn pieces of felt, the corner of the heel forms and edge that "grabs" onto the surface of a rounded rock and gives you a stable hold on the top of the rock.
I tested wading boots for Weinbrenner and they were thinking of importing cheaper boots with one piece soles, and I fell wearing those boots on rounded rocks. I dinged up my new Ross Evo reel as well. I told them the boots were junk.
The boots even had studs but the stud pattern was wrong and they projected way too far out of the felt. The stud pattern must allow both felt and studs to contact the ground/rocks. That way, when you are on a rock, you are not on just the tips of the studs.
The bottom of the Borger boot shows that the area under the ball of the boot has no stud but as you rock your foot forward, the studs begin to grab. Also notice that on the side view of the boot above, you cannot even see the studs because only the tips project from the boot. As you step on the felt, the felt compresses and the tips of the studs contact the rock and river bottom.
It's not the felt, it's the design. You can't just put a layer of felt on a one piece sole with a rounded elevated one piece heel and expect it to grab the top of a rounded rock. Note that the felt of the Borger boot is not only glued to the welt but sewn to the welt.
Quality boots cost more but if they save a fall, they are worth it. I wish they could make them lighter but these boots last forever. I was a tester for the the prototypes of the Propex (ballistic nylon) boots above. I still have them and they are going on 10 years although the need new studs and soles. The boots are solid and have not blown out the sides or the toes.
Regards,
Silver
"Discovery consists of seeing what everybody has seen and thinking what nobody has thought"..........Szent-Gyorgy