In fairness, this amortization assumes only applying the R&D research projects, which are material-efficient, but not time-efficient.
Using the crafting projects for leveling apply a standard rate of 10 XP/min, whereas the research projects apply 5 XP/min.
Granted, one can't be camping the R&D interface for 24 hours a day, but the balance of additional R&D slots should help with that, especially if one is concentrating on only one or two schools on a character at a time.
As for materials efficiency, the research projects only require a single Common (white) material to operate, whereas the crafting projects clearly consume substantially greater.
Add to that the XP-rich, long-term upper-tier crafting projects (Mk8 and up) require Rare (blue) or better mats, so that balance of resource availability is going to need to be factored in, especially at higher levels.
Obviously, spending dil or Zen is incentivized throughout the system.