Seat64A

I recently received an email from Skywards which claims to be describing an enhancement to the "seat guarantee" benefit for Gold members.

The core of this "enhancement" is as follows:
"From 15th August 2014, you will no longer have to wait for a flight to be full to book a guaranteed Economy Class seat. We will now confirm your seat when the cabin is full."

I cannot see how this is an enhancement. If you do not "have to wait for a flight to be full to book a guaranteed Economy Class seat" where's the benefit, as anyone, Skywards Gold or not, can book an Economy seat on a flight which is not full in that cabin?! Why would anyone wait for Economy to be full before booking if he/she could book earlier?

I am genuinely puzzled by this email. Does it mean that, for example, if you want a J ticket but that J and Y (but not F) are full (and therefore the flight is not full), you are now guaranteed a Y seat, whereas previously you weren't?

Am I missing something here?