My unicorn card is current in its pen (safe deposit box at the bank) for the winter, haven't charged more than $50 in any month in the last six month if not a year and in the card's 3 years of history its only seen a maximum monthly spend of perhaps $1100 when "packs" still existed, and , typiical charges are $14.95 myfico subscription, so I had just paid off the $14.95 balance then hit the check spend button for $5k appoved, so they don't consider non-use a reason to reduce your internal limit as long as you have good payments on your other AMEX cards.
So you're saying playing with its magical "horn" (occasionally) won't put a bad spell on spending... LOL. Since it's not my primary AMEX for usage and I may charge on it here and there, I don't even recall the last time I checked the spend button.
i hadn't used it in a while, my previous tests were to try the button when there was a $1000 balance on the card and request a $2k purcase thus testing if $3k would work, and then a few moments later PIF and never make the large purchase. Perhaps next month I may try $10k just to see if works with no intention of making the purchase.