I came here to make the exact same comment. Looks really nicely cooked, but tri tip is odd to cut because the grain changes direction. Here's a pic of the way to carve it.
Yeah, that was my mistake. I don’t usually carve while talking and I was over half way through before realizing I’d cut straight on instead of a more “angled” approach.
If it’s any consolation it was still cuttable with a fork’s edge!