The US state department contains this confusing statement that implies that there is an additional 90-day waiting period before I can restart a 90/180 Schengen visa. This does not match several other posts on this site.
If you spend three months in the Schengen area during any six-month period, you must wait another three months, from the last date of departure from the Schengen area, before you can apply to enter the Schengen area again without a visa. If you do not meet these conditions, or if you plan to stay in the Schengen area longer than three months, contact the embassy of the country where you plan to spend the majority of your time to apply for a visa.
Could anyone provide any insight? All of the other posts seem to indicate that a second 180 day period could begin immediately after a prior period ends.