Final answer:
The use of lightweight concrete is not a method for speeding up the process with formwork for sitecast concrete; it pertains more to the material's characteristics than formwork techniques.
Step-by-step explanation:
The methods used to accelerate the process of sitecast concrete do not traditionally include reducing the weight of concrete as a formwork strategy. While it is true that the use of lightweight concrete has been employed for centuries in construction and particularly over the past century, has seen advances in reliability and predictability, this pertains more to the material's properties rather than formwork techniques. Lightweight concrete is a mix of light coarse aggregates, like shale, clay, or slate, which indeed provides benefits such as reduced load, faster building rates, and excellent thermal protection, advantages that make it preferable over heavier materials like brick. However, when discussing formwork methods that have evolved to speed up sitecast concrete processes, we generally refer to improvements in the molds and structures used to shape the concrete, such as using prefabricated forms, slipforming, climbing formwork, or using formwork systems that can be quickly assembled and disassembled.