A couple of weeks ago, Apple began pushing a new iTunes feature where customers who had only purchased tracks from an album could download the rest of the songs for a fraction of what it would cost to individually purchase the remaining tunes.

Called “Complete My Album,” the marketing ploy was just starting to gain traction when the first rumors of a major announcement from Apple and EMI about dropping anti-copying protections started making the rounds.

Here’s how “Complete My Album” works:

ITunes customers who have already purchased single tracks from an album can apply the cost of those tracks – 99 cents per song – to the purchase price of the entire album. That is, if the customer completes the album within six months of buying the individual tracks.

Because most single albums on iTunes cost $9.99, this can work out pretty well if you’ve already bought one or two tracks.

But you might want to do some math before you fire up iTunes to fill in the gaps in your music collection. That’s because “Complete My Album” is only a bargain when there are enough songs on an album to make individual track purchases total more than the offered discount.

For example, an iTunes customer purchasing two tracks from a 10-song album will end up spending $1.98. If, after purchasing the tracks, the user decides to buy the remaining 8 tracks from the album, that $1.98 will be deducted from the $9.99 purchase price, resulting in a $8.01 price tag.

But buying those remaining 8 tracks at 99 cents per will cost $7.92, so the “Complete My Album” deal isn’t all that special.

But if the customer has previously purchased, say, one track from a 12-song album, he or she can purchase the rest of the album for $9. That’s 99 cents less than iTunes’ $9.99 per album price and almost $2 less than if the customer chose to buy the tracks individually at 99 cents per. So you have to consider how many tracks are on the album as well as how many you’ve already purchased in order to determine if “Complete My Album” will save you some dough.

Nevertheless, since iTunes has been accused by both music lovers and music industry members as being partly responsible for the slow death of the CD, any marketing ploy by the computer / entertainment company designed to sell albums can hardly be a bad thing.

“Once we bought a song, we wondered why we had to buy it again if we wanted the album,” iTunes VP Eddy Cue said. “We hope it helps us sell more songs ultimately, and from the customer point of the view, we think it’s the right thing to do.”