No... I believe the "save xx%" shown for the rerfurbs at the Canon Online Store is merely comparing the price of the refurb vs their "street" price for the lens brand new, elsewhere on their site.
They do have sales and offer add'l amounts off refurbs occasionally, and/or free shipping offers. It sort of depends whether they have a lot of refurbs in stock or not. Their inventory of refurbs sometimes spikes shortly after a big event where Canon Pro Services was providing support or a big photo show where they used a lot of demo units. This would be largely limited to events and shows in N. America or the U.S., since the store is here. It also occurs when new models roll out, probably when dealers return a lot of out-of-box display models. Recently the 7D refurbs were pretty steeply discounted, which might indicate they are drawing down stock anticipating rolling out a 7D Mark II in the coming months.
CLP is somewhat different... though it seems to tap into the same stock of refurbs. Search here for more info. You have to call them and find out what's available and if your trade-in qualifies... The CLP discounts are usually greater than the refurb sales prices, but are also limited by availability.