> almost like they just didn't keep track of how much R&D they did for each item. That’s often almost the whole point! Tracking the R&D effort for each item i

> almost like they just didn't keep track of how much R&D they did for each item. That’s often almost the whole point! Tracking the R&D effort for each item in the repair kit would add an enormous amount of overhead and accomplish essentially nothing. The numbers will be wild guesses and you’re going to have to make tons of ad hoc decisions about allocation anyway. Suppose you tweak the design so it a part can be attached with a special pin rather than a screw and spend an hour testing it. What’s the “right” allocation of time to the pin, hammer, part, and screw (that you’ve eliminated)?