Well, not only is there no progress on this, but Customer Support has taken to offering the same workarounds noted above ("Just add some custom text that lets your customer know that the coupon code is entered on Step 2") * or, worse yet, shilling for $17/month third-party apps that are still just workarounds and not fixes to a broken process. Poor workarounds at that, since the app that was recommended was for quantity-based price breaks.
If your customer experience relies in any way on coupons or discount codes, don't expect Shopify to meet your needs.
* Since they're suggesting our own workarounds, at least we know that someone at Shopify does read these threads, right?