You can fix it.

I have the aluminum version. Ritchey WCS seatpost. On the first ride, I hit a bump, and the saddle tilted all the way back. Grrr. I tightened it more, and it did it again a couple of rides later.

I made a few mods to the clamp that fixed it. It's been fine for a couple of years now, no slippage.

The top of the seat post is curved to allow the similarly curved clamp to tilt front to back. The surface had been roughed at the factory, but the contact points were shiny smooth, especially after the forced tilt on my ride. There's a wedge piece with a hole for the bolt that bears against the bottom of the seat post top piece too.

I used some 180 wet-or-dry sandpaper to score the contact surfaces, mostly side-to-side. I did the seat post top, the clamp, and the wedge. I did it just enough to make the surface rough--not enough to change it's shape.

The removeable top clamp showed the small shiny patches where it was contacting the curved seatpost top, not covering the whole surface of the clamp, so I sanded down those high spots a little more--just a little-it doesn't take much to sand aluminum.

I put some carbon assembly paste on the surfaces. I grease the bolt threads, keeping the grease off the mating surfaces. I crank down on the two bolts with a small L allen wrench, pulling hard on the wrench, and alternating the two bolts. The wedge pieces say "16 nm max" on them.

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It's not the best design. It's a simple, elegant looking clamp, but it critically depends on the friction of the components. I thought it would be good for micro-adjusting the tilt, and it does, but it's fussy to get it just right as the bolts are tightened.

I needed this post's 25 mm setback. The front-to-back 2 bolt posts I found were mostly 10mm or less setback.