Yes, but the overall we get "more power out of the building then we put in" isn't the goal. They are trying to drive the Q factor of the reaction itself up. If they get that to > 5x what the laser strike hits (a very real probability) it's likely trying to make a building that has a net positive Q makes sense.

That building would use modern lasers, modern supercapactiors, etc. to significantly change the "other" parts of the equation.

This is like making a program work on your laptop, but realizing that scaling up to production with 1000 laptops would be too costly, so you use actual servers. But you are in no rush to code directly on a server machine.