Reply to Questionable R&B mixing method.

So I'm working with this other DJ right, and he doesn't play below 133 BPM at all, even deep house tracks (Disclosure's White Noise really does show the horrors of +10% pitch increase) and I jumped on cause it was my turn, and I mix in an R&B song at 104 because, you know, it needs to calm down. Then I start looking through my library of which track to drop next when he stops me and starts schooling me on how to DJ urban (Bearing in mind I have a Kontrol F1 loaded with a RnB mashup clips, and an extensive R&B library, and am a massive fan of R&B)

So, his theory goes like this, (and apparently this was taught to him by a pretty well respected R&B DJ) that whe nyou play a track, say 104 BPM, then all the tracks you should mix into it should be lower than 104 and sped up, basically that you NEVER slow down a track to beat match it. Apparently he worked with two other DJs who also verified this and used the same method.

Now, did I miss something, or do Technics and Pioneer make the pitch fader go both ways just to mess with us?