The Battle to Show Discounts

I've spent today re-doing the discount structure on the website. This is one of those areas that always seems to be hard to do exactly the way you want to. Previously a customer had to enter their delivery details to access the discounted prices, which I felt was putting people off. We weren't asking them for anything other than info we would have had to have had if they bought but it seemed to stop people in their tracks. In Interspire, variations of size or colour to an item make dealing with discounts quite restrictive so I'm having to go through the catalogue and the variations altering prices item by item. It's laborious but at least you end up with the discounts you want on the items you want them on!
If anyone reads this and has a way to apply a percentage discount to products and their variations without having customers register first, Id love to hear it!
A man takes his son to the zoo. They pay their money and go in but find that the only animal is a dog in a cage. The man storms back out to the entrance to complain. "Call this a zoo? It's hopeless! There's only one animal and its only a dog!" The guy on the ticket office turns to the visitor and says, "Yes! It's a shitzhu!"
Ho Ho Ho