The fact that a 250 (approximate) cubit distance may have been intentional is a primary level speculation in and of itself.
Attaching any meaning to it requires layering speculation upon speculation. That is unacceptable methodology.
To put it succinctly, even the 250 cubit measure is in serious doubt.
Allow me to explain clearly how the geomancers derive it:
They start with Petrie's survey data - fair enough - and then divide that by the value for the cubit derived from the King's Chamber. The problem is that the cubit was variable. Petrie's data showed that it varied at Giza - by about 1% - and the surviving cubit rods - see Arnold - show a similar variability of about 1%.
That means that a tolerance has to be applied to all the cubit values the geomancers quote. 1% of 250 cubits is 2.5 cubits. There's a 1000 cubit diagonal that they can "find" at Giza - which should have a tolerance of 10 cubits. That tolerance then has to be added to the tolerances for technical accuracy that we know they had (such as the sides of Khufu's pyramid being off by 8 inches in only 756 feet).
In reality it's clear that the position of one pyramid wasn't set a certain number of cubits from the previous one - as there was a temenos wall round the pyramid and then another one further out enclosing the pyramid and the surrounding cemetery. If it was measured from anywhere it would have been from the outermost wall and would have been based on what had been decided for the overall size of the pyramid complex.
Petrie's variable cubit at Giza must also be close to proof of no overall plan. The values are so loose that determining a "plan" is inconceivable. The variation is invariably used as a tool to allow more and more Brilliant Speculation to float around on the internet. Plain and simple.
Anthony
You can lead a horse to water but you can't make him think.