The Grid Method was invented as a response to the Company fracturing, leaving a workshop without a designer. In response, somebody (John Harrison, John Hurst, or William Potts) invented the Grid Method, where a glass-cutter could make a nice window without any advance plan. This clever method cut out many stages, simplifying the work just as much as skipping painting did.
The main trick was to pave as much of the surface as could be passed off with 2 3/4” squares. By using standard straight-sided pieces, shunning painting, skipping design itself, and not talking to the client (who was a builder, and didn’t care anyway so long as it got done), our heroes ended up with a high-speed cheap product that could be used to wedge the market open.
Among our candidates, John Harrison is the candidate of opportunity, having been Cutting Manager on the day the company fell apart. He was indeed a cutter without designs, which is what the Method addresses. But John Hurst is a better candidate, because his career led him from design onto the shop floor, where (I suspect) he ran off hundreds of these in the next three years. William Potts is also a candidate, but based on his longer career I find these early ones too serious, and too carefully measured, to be his style.