I only found one reference to this and the thread was closed without an answer.

I repair dvds (games, movies, etc.) and offer two ways of shipping. Either I respond to an order by shipping a mailer or the customer chooses to send it immediately and i ship it back. This means two different ways shipping is calculated.

I use a table now for my mailer shipping rates but can't find a solution for the reduced shipping costs of option two. I've tried attributes but it becomes complex and discounts are applied to each unit instead of total order, I've considered coupons but it's also complex. I'm sure continued efforts will yield something but I'd rather have a separate shipping option.

So is this possible? Can i clone and rename the shipping table module?

Thanks