The stated purpose is to help assign certain costs to the customers whose needs cause them. [L07/LE07]
That is evidence of a regulatory mechanism. It is not evidence that a particular residential bill has already gone up, gone down, or been fully insulated from every effect of new demand.
Cost allocation is a mechanism, not a promise. The central reader concern is often short: Will I pay for this? The responsible answer is longer. In Virginia, the State Corporation Commission describes a framework for large-load customers that includes a separate rate class, minimum transmission and distribution cost obligations, collateral requirements in specified situations, and direct-assignment policy work for facilities that would not otherwise be needed without a large customer.
In its rate-case materials, the Commission and its staff have also treated forecast assumptions and the alignment of projected investment and revenue as matters requiring scrutiny. That is precisely why a reader should be cautious about a single before-and-after claim.
The bottleneck isn't steel or silicon anymore — it's the multi-year wait for a signed interconnection agreement.