There is no golden rule how to proceed with this. Sometimes you will find unique strings that hint at a debug menu (like talk about warps, events, etc.). Other times you will debug a totally different routine and just wonder what that one flag does that's never set and bam a menu opens and you're set.
As for feasibility, it depends how extensive the menu is. If you can warp to all places, buff up your team etc, it's great. If it's just some sound control or color changing, then it's probably not as useful. It can't hurt to know how to enable one if present and to translate it properly for posterity's and your own sake, though

cYa,
Tauwasser