And a lot of them do little to disprove that. Just as many creative boutiques are actually full of pretentious popinjays and deluded dilettantes. But I've been travelling a bit recently, meeting some people on the edges of these networks, and it's forcing me to examine those assumptions.
The first thing you notice is how much higher the level of technical difficulty is for a big, international business that wants to do great work. The tensions of its sprawling structures and huge departments are exacerbated by multiple and contradictory responsibilities - to local and international managements, to clients and to shareholders.
These things are not the result of stupidity, they're inevitable responses to the world that created these networks. And those of us who carp from the chaotic sidelines of small, creatively focused, founder-led organisations should realise how much easier we have it.
But all this unhelpful scale has led many to assume that the end of these juggernauts is nigh and, if you only see the New York and London politics and posturing, that seems like a reasonable assumption.
However, when you get to some of the distributed outposts, you start to see different and exciting possibilities for these businesses, especially if they can reorient their relationships with the world.
Think how potent a network could be if it could harness the creative energy and originality of markets such as Argentina or Romania and point them at global accounts. If you've grown up producing work for a market as diverse as Lebanon, how interesting would your working assumptions and habits be when applied in a different context? If you're a man who's learned how to market feminine hygiene in a country that doesn't allow male researchers to talk to female respondents, you're going to have a bunch of interesting research techniques to offer the world.
The classical planning discipline is largely the way it is because it grew up in the UK, where most clients only did one big TV campaign a year. So it had better be right, and you could take a long time making it. What will planning or media thinking be like when you have third-generation planners who have grown up in completely different markets? And most of all, imagine the potential for valuable disruption if these networks turned themselves into conduits for local talent into the global creative economy, rather than distributors of centralised thinking and ideas.
Maybe they're already doing it. I hope so. Because then big would equal interesting and I'd have to eat some cliches.