I find the 3 flash 'lane change' quite annoying on motorways. I was always taught that the number of flashes should mirror your speed, i.e. at 70, you should give approx 7 flashes starting from the centre of your lane until you're fully in the desired lane, 6 at 60 etc etc. The 3 flash is only really good for around town driving. Overtaking on a NSL A or B road, and they're perfect...but that's probably the only time I think they're any good.
Half agree with you here .... motorway bit I fully concur .. but the "around town" bit I don't ....
Indicators are exactly what they are called ... they "indicate" your intention to move .. they are not a statement of fact .. "I am moving" ... they therefore need to be seen BEFORE the event .. not during it.
It is easily argued that with the additional distractions to ALL drivers of other vehicles, pedestrians, traffic lights etc etc .. that MORE use of indicators is better, rather than less. 3 flashes are pointless as they may well not be seen by a driver watching a pedestrian with a pram as an example.
The old adage .. Mirror, signal, manoeuvre, cancel, seems to require a few more than 3 flashes .. less than 2 seconds

?