Place these numbers in order of largest to smallest: .00156, 1/60, .0015, .001, .002
One sixtieth is the biggest of these, as the others are between one and two one-thousandths (or between one one-thousandth and one five-hundredth).
Then, in descending order, we have .002, .00156, .0015 and .001.
It is common that students will order the decimals this way:
.00156, .0015, .002, .001
I cannot predict where a person who does this will place one sixtieth.
Nonetheless, when we read these decimals as point zero zero one five six, we encourage students to ignore place value, and we encourage the misapplication of whole-number rules to the right of the decimal point.
We really do need to use place value language for decimals in classrooms. One-hundred-fifty-six one-hundred-thousandths.
Much, much more about this and related ideas in the Triangleman Decimal Institute posts from last fall. Short version: learning decimals is WAY more complicated than most people have any reason to imagine.