Well you can thrown out the theory that what you spend your money on makes any difference to whether you get an offer or not.
I just got the black envelope this afternoon. I have been an Amex member for a whole 13 months and in that time I have spent about $260,000 on the plat charge and another $55,000 on the plat CC you get for free with it.
However, no more than about $20,000 of that $315,000 was on anything that you could describe as luxury spending - some international airfares, hotels and resorts and the damage done by my wife's raid on the Fendi boutique in SIN. Almost all of the rest was obvious business spending - ATO tax payments and various professional items and services.
I think I will give them a ring and see how they can sell the extra $3400 over the plat charge as being worthwhile.