This first video shows the trimming of a pretty well maintained "vertical" bar.
The second video shows bar that is a bit more "overlaid" or "embedded" and how I would trim them differently.
I try not to get too hung up on the "type" of bars, but instead just try to trim the bar to match the solar concavity and to allow the bar to function as it should - to help structure the shape of the back of the hoof and the collateral grooves. .
Kristi Luehr is a barefoot trimmer/farrier, author, and founder of the Okanagan School of Natural Hoof Care. She is certified by the Canadian Farrier School as well as the Oregon School of Natural Hoof Care, and also has certification in equine massage and dentistry. Her focus is to educate owners about hoof anatomy, function and proper barefoot trimming that supports and grows healthy and functional hooves specific to each horse's individual needs. She is the author of three online courses specific to hoof care and is always striving to create more educational content for students to learn from.