Not 100% certain I am fully understanding, but it looks like slippering may may be another term for beveling the heels?
A member named Patty was here when I first partnered with Hondo and she recommended beveling his heels to encourage heel first landings. I was making slow motion videos of Hondo's feet at that time and it did seem to help.
Patty was very much part and parcel to E.L.P.O. at that time and my still be. She was an extremely knowledgeable farrier with wide ranging experiences.
I've actually been using that technique recently as my laminitic horse's heels got away from me during episodes of hoof pain. I also look at it (correctly or incorrectly) as a way to gradually bring the heel back down allowing time for internal adjustments to slowly take place.
I have also used a variation of this technique on my Navicular mare. One thing I will add is that as the BLOG mentioned there were 3 trims in a 3 month period of time - that keeping on top of the growth to coax it the right direction is paramount to making this process work
Yep, bevelling the heels is what most call it I think - 'hoof slippering' made me think this was about a 'slipper footed' - aka chronic founder - horse.
Yes, in many instances, for a number of reasons, it is not possible/helpful to lower the heels too much, and if heels are 'run forward', bevelling the back of them, so you can relieve the crushing & allow them to 'relax down' more vertically & further back, but without lowering the foot angle is helpful.
What I find also helpful is to provide flexible support under the frog too, to allow that to comfortably take more load, which relieves the heel walls further, allowing them to 'relax back'. And of course, keeping the toe back to where it should be will also help avoid/correct 'run forward' heels.