These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Subnormality
Anvilicious: Ooh boy. Let's just say Rowntree isn't a big fan of subtlety. See also Author Tract and Author Filibuster. It's nigh-impossible to find a strip that's not delivering a heavy-handed message about something or another.
Most strips are less telling the viewer to take a specific path in life, and focusing more on observationalism.
Genius Bonus: Applied fairly often, such as here. The "16th century Russian howitzer" is in fact the 1586-built Tsar Cannon, and can still be found in present-day Moscow.