There is essentially, IMO, NO standard form technique... It is like askinh which is better for self-defense? Karate or Kun-Fu?
Technique depends on several factors, ie., type of bike, rider skillset and experience, type of riding, rider personality and tendencies, time of the day/weather, riding environment, etc. Some schools teach it; while others do not... But it doesnt mean it is _absolutely_ wrong.
Personally, when in the twisties/canyons in Japan, or once in Southern California - I tend to trail brake. But when I did the 2-Day Camp in Las Vegas last February - no trail braking... Just a quick turn in, straighten the corner, then roll on the throttle...