This! That's the surefire best strategy for guaranteeing an empty seat next to you.

I've seen instances where one could buy three seats in Y for less than one seat in F. I'm all for paid F, but sometimes "EXST" in Y is the better strategy and the better deal.


Edited to add: if trying to book 3 seats for extra space I'd be very careful about booking an exit or bulkhead row lest those rows have the hard partitions between seats. You'd want a regular row to be able to flip up the armrests and make the poor man's sleeper seat.