As with everything YMMV but when I applied for my second 3x CLI I had optimimised my card reporting and overall utilization (I always PIF but I let my balances report every month). When I checked Experian AMEX hadn't sp'd me since July when for their purposes I had roughly $10k reporting. I applied anyways and was approved for an increase to $18k. I feel many people on this board put a bit too much emphasis on SP's and optimising your score to appease the credit card gods at AMEX.
Amex BCE 24.5K | BofA Cash Rewards 15K | CSP MC 13.5K| Chase Freedom 7.5K | Discover IT 3K