I have a smaller area on my neck that is extremely prone to razor burn and ingrown hairs. The hair there does grow in an odd direction. I have to shave very lightly there and only accept WTG. And in that area, WTG is shaving upward toward my chin and at an angle.
If you continually have razor bumps/burn, I would venture to say that you're shaving over ingrown hairs. The "bumps" are the skin, and the actual whiskers, unless released from underneath the skin and allowed to grow while the skin heals, are buried. So, when you shave over this area, you continually abrade the actual skin without getting to the whisker.
I have my best luck at avoiding razor burn in that neck area by using a straight. Even so, when I hone a razor and test shave, if the edge is harsh at all, the patch is angered. I have to then take a pointed tweezers and pick each whisker to the surface and let the skin around each follicle heal for 3-5 days. Then it's easy does it shaving that patch and everything is alright.
Chris L