there are other parents on this forum (not only this thread) who have taken a place but are apparently not definitely intending to send their child to the school. And seemingly others are also encouraging those parents not to let the school know if they are arriving or not.
If those parents are waiting for the state allocations day or are on the waiting lists for other independents, then I join those encouraging them not to let the school know. CLSG set the rules of this game. You can't fault parents for playing by them.
After last year, the school made less offers but I'm guessing that the 9 hour explosion will have been fuelled (in part) by some parents rushing to encourage others to take a place 'just in case'.
I'd be surprised if this weren't the case. The logical equilibrium for this game that CLSG have set is, indeed, that any accepted applicant with the wherewithal and any potential desire for the school must queue up at the first possible moment - just like for tickets to a sold-out concert. The only reason that didn't happen this year is that relatively few people thought it through to the conclusion.
The fact that CLSG are surprised at this outcome indicates that either a) they didn't think it through themselves, or b) they did understand the consequences and, having already screened the girls, they decided to screen explicitly for parents who worked through the game ahead of time. And/or for whom it was the first option. And/or for whom it was the only option. And/or for whom £1500 was immaterial.
Every allocation mechanism has drawbacks for somebody. At the NLCS open day last spring, a question was asked about exploding offers. The head of admission replied, "If too many girls accept our offers, that's my problem, not yours." CLSG have chosen to make it your problem.
If I were to be mean-spirited I might even suggest that any parents, who have put down the £1500 but then receive a more preferred place, take their time and inform CLSG on 17 April rather than on 02 or 07 March. After all, you've paid for the privilege of making it their problem. But, unfortunately, that would also have highly detrimental effects on girls on the CLSG waiting list who really want the place, so let's not go there.