Simple delivery might have had a chance of working if the Royal Mail had kept their old pricing method - by weight alone.  When you've also got to start measuring-up then that's when things get complicated.  The worst thing about SD is that the ebay robot thinks it knows everything about the item you are trying to list, or your personal circumstances in being able to drop-off the package within a limited time allowance / wait around all day for a courier pick-up; (it doesn't).

It appears that SD will now be compulsory in the New Year.