To be honest I would prefer paying for it once and then using it nonstop for free(also that it would perform on paar with other non doc on map solutions of other factions) than this shite(also 45 muni per pop isnt that cheap if you add it up).
Also americans get free officers and they are extremely useful(When they tech up).
Now its pretty much you get it for free, also its shite and you have to pay 45 muni that could be used somewhere else. This also makes the Artillery doctrine shite.
Compare it with other 45 muni abilities - bundle nade, guards nade and now tell me again it's underperforming for its price. If you stay in barraged area you will take damage or lose squads. However I think going artillery regiment should give buffs to the 25 pounder artillery after a resource upgrade.