One of the problems with many gardening and horticultural articles are that they are written by professional writers - not horticulturalists. When I read something that is stupid like this, I check the persons Bio and it usually says they began their writing career, blah, blah, blah after receiving their degree in Ancient Roman History or whatever. Not Botany, not Hoticulture, etc.
There are a bunch of sites telling you how to grow seeds. They all have the same boiler plate info - much of which is wrong.
These guys are among the worst with crummy advice.
homeguides.sfgate.com
Horticulture magazine SHOULD know better.