There's another error I sometimes see on the board or in SPs' advertising that I feel stems from not being informed of the difference between "discrete" and "discreet."
From dictionary.cambridge.org, American English:
discrete: "having an independent existence or form apart from other similar things; separate:
This area has four discrete neighborhoods centered around a school."
discreet: "careful not to cause embarrassment or attract a lot of attention:
She hung the laundry on a line in a discreet corner of the yard.
There was a discreet knock on the door."