I linked to that to show that the OC edition GTX 660Ti and HD 7950 (as used in the TR article referenced by the OP) use similar power. The only time a HD 7950 will consume significantly more power is when the voltage is increased to 1.2 volts or more. Even then it is still significantly less than previous gen GTX 580, so some perspective is required when judging power consumption.
Here is a list of power consumptions for various GTX 660Ti cards compared to a reference HD 7950. Under full load a reference GTX 660Ti consumes 29 watts less power than a HD 7950. Hardly a massive difference is it? This of course only applies to those who purchased stock clock 660Ti cards. If you purchased an OC edition then congrats, your card is drawing the same power as a HD 7950 but you have significantly reduced OC headroom.
http://www.hardwarecanucks.com/foru...roundup-asus-evga-gigabyte-galaxy-msi-22.html
At least there is that option on the HD 7950 to use more volts to attain significant overclocks. 800Mhz stock to an even moderate 7950 overclock of 1100Hz = 37.5% overclock. 40%-50% overclock on a HD 7950 leaves a GTX 660Ti in the dust, in fact it even exceeds a GTX 680 overclock as shown in my link. An overclocked GTX 660Ti does not even reach stock GTX 680 speeds for current gen games, let alone compete with an overclocked one.