In my experience of detailing, personally I have always used Megs APC and a cloth...the amount of crud that comes off the seat is unbelieveable! This in itself, is more than enough to give the seat the original matt appearance and how I left my leather seats...its lasted around 3-4 years now and only now, does it need another clean...I have not touched them inbetween...just simply driven the car!
The Dr Leather Wipes are amazing at cleaning the seat and do also give the same effect as above...ive also known detailers to use these with zero issue and like myself above, dont need to 'seal' the leather
Anti friction idea is good, but in the real world, I have found alot of creams etc for leather make them shiney...exactly what I dont want lol im sure they have come a long way since I last used Gliptone, but I wasnt really a fan...and like you said, the leather actually doesnt need sealing...and an anti scratch coating might be the way forward (not that I have ever scratched my leather)
In detailing, I find everyone has their own way of doing things...there are a million and one products out there that ultimately, do the same thing...it just depends what brand you like, and what your methods are
