In 2014 Westinghouse still touted high confidence in affordable, predictable construction for its Generation III AP1000 design:
https://web.archive.org/web/20141225195417/http://westinghou...
From the outset, the AP1000 PWR was designed to reduce capital costs and to be economically competitive with contemporary fossil-fueled plants. This requires lower overnight construction costs and higher confidence in the construction schedule.
The AP1000 plant reduces the amount of safety-grade equipment required by using passive safety systems. Consequently, less Seismic Category I building volume is required to house the safety equipment (approximately 45 percent less than a typical reactor). The AP1000 plant’s modular construction design further reduces the construction schedule and the construction risks, with work shifted to factories with their better quality and cost control as well as labor costs that are less than those at the construction site.
This also allows more work to be done in parallel. The use of heavy lift cranes enables an “open top” construction approach, which is effective in reducing construction time.
With new computer-modeling capabilities, Westinghouse is able to optimize and choreograph the construction plan of an AP1000 unit in advance by simulation. The result is a very high confidence in the construction schedule.
In actuality, AP1000 construction went so far over budget and behind schedule that it bankrupted Westinghouse 3 years later:
https://en.wikipedia.org/wiki/Westinghouse_Electric_Company#...