good question Terri
as I understand it, its a range, from .4 to .6

when I started off we always mentioned it as .6, but if theres one thing I have discovered its how flexible the steps are for the individual . So yes shared experiences have meant that a range can apply

I aim for the .6 because my body says thats best for me.. .4 has me a bit nibbly, and theres a lot of scope with a range from .4 to .6, to build up and see what suits one best