The older structure worked when the entire Vandal mech regiment moved in a single fleet. Lower-ranked mech designers could turn to plenty of Apprentices or Journeymen for assistance.
It worked best with better-funded mech regiments. Unlike the Vandals, the other mech regiments employed an ample amount of mech designers. With up to a hundred higher-ranked Apprentices and up to twenty Journeymen employed at a time, a mech regiment did not lack for design muscle.
Even if most of them would spend their time on tinkering with actively developed mech designs, that much mech designers may still be useful even as tech support from a distance.
Besides, Ves bet that the other mech regiments also employed a lot more lower-ranking mech designers as well. Perhaps ten or twelve of them might be assigned to each combat carrier. If they were allocated in a clever manner, their diverse specialties enabled their team to cover a wide spectrum of possible problems.