Normally, for the average crowd, one would not drill a pearl pin down, especially one with a high rg. It has the tendency to burn off tilt too quickly and save nothing for the backend especially as bowlers move inward to chase oil. Essentially you'd be making the pearl into a solid. Thats where people pop 10's and complain that the ball sucks. And for the most part, you pay for a pearl because you want length and backend recovery when the solid is to much up front and not enough on the back.
In this case the Pearl uses a low rg core which helps get the ball started so i dont really see a problem with it. I have one and its drilled 45x4x35 which puts the pin above and slightly to the left of my ring finger (being left-handed). I love how the ball TRULY reads the mids and flips over, whereas, most pearls with a higher rg, like the fire road, are harder to read where the ball is going to hook.
Understand, the Pearl was made to be the "pick up point" from the solid. What I mean by that is, as stated above, when the solid starts popping corners because it doesnt have enough to corner, the pearl will pick up where the solid leaves off. The pearl is one of the most drillable balls ever. I done and seen everything from 6"pin to pap's to double thumbs and everyone has loved them. I see no problem with drilling it pin under to be a 1-2 combo with your solid.