THAT IS NOT TRUE.
English Advanced has a LOT higher scaling than English Standard.
In fact, even English ESL scales higher than standard.
http://www.uac.edu.au/pubs/pdf/tsc_report_2007_fin_web-sep.pdf
Quoting from the above UAC article,
English Standard
HSC 32.8
scaled 17.7
English Advanced
HSC 39.5 3
scaled 31.2
English Extension 1
HSC 39.4
scaled 36.3
English Extension 2
HSC 40.1
scaled 36.6
English as a Second Language (ESL)
HSC 35.9
scaled 21.4
Page 38, if you don't believe me.
Hence, the higher level of english you do, the better scaling you will get.