by fruityharris
I think OP means upgrading digging. Yes it's rare to do this in r1 or r2, but it can often be a brilliant tactic oh the midgame. (For some factions more than others, e.g. Halflings, chaos magicians, swarmlings, often witches.)It took me a lot of games (maybe 20-30) to appreciate the value of upgrading digging, and I think that's partially because it took me that long to become sufficiently good at building my economy for it too actually be worthwhile.
In beginner players there's a gradual transition away from early strongholds to early temples, and harnessing the power off advancing digging and shipping is the logical conclusion of that.