Have you tried taking a knife down to less than 25 degrees inclusive? Here's a post I made not long ago about the Caly 3.5:
Some steels, properly heat treated, can take and hold a more acute or narrower angle than other steels. The thinner the angles - not just at the microbevel, but also at the bevel and the primary grind - the thinner the blade is behind the edge. Sharpness can be achieved even with a 90 degree inclusive angle: glass typically breaks near that, and glass shards are plenty sharp enough to shave with.
Think of cutting something as rolling a 200 pound cart up an incline of a fixed length of 20 feet. You can roll the cart up a 20 foot long 45 degree slope (your knife), or you can roll the cart up a 20 foot long 20 degree slope (my knife). Which one will be easier to roll the cart up?
Interestingly, in some cases a knife doesn't even need to be sharp to cut. Box cutters are typically pitifully dull, but they still are able to be used to cut cardboard even when dull due to the edge geometry of the blade.
Hard, tough, and strong steels can take a more acute angle while still retaining all the toughness of another steel at a more obtuse angle. If you appropriately use the correct angles and grinds for different steels, you can get an enormous increase in cutting potential without losing much of anything in the process. In fact, there are a few videos on Youtube showing that two knives with the same steel and heat treat, but one has narrow bevels while the other has thick ones, are pounded through some copper pipe. Interestingly the knife with the thinner bevels did better because, it seems, that less force was required for it to cut through the copper pipe.
