short answer: no.
unfortunately, discount codes will no longer be retroactively applied to orders. in the case of a sitewide discount code being available, the code will be found on the welcome banner of the website home page, as well as the announcement banner found on the top of every page accessed. i hope to also add a notice on the checkout page reminding customers to input any discount codes they may possibly have before completing their transaction. as such, since sufficient notice is given throughout the website concerning coupon codes, the decision has been made to no longer apply them after order completion.