In social network theory it's commonly noted the disproportionate power wielded by 'bridge' nodes which link different clusters (in this case teams). So it's not just that people who can't do technical work become glue people, it's often a savvy move in a bureaucracy. Indeed a standard move to increase your power in an organisation is to increase your betweenness-centrality, e.g. managers will actively foster silos because being at the head of a silo means you're a powerful conduit between that silo and everywhere else.

On another note, I've seen in government that there is an exponential growth in not just glue people but glue teams. Here the problem is obvious, the bigger an organisation is, the harder it is to ensure adequate communication between teams working in similar areas because there's so many teams to keep track of. Whenever a communication failure occurs, someone puts their hand-up to make a glue-team, a manager thinks 'this will fix this problem', and thus a new team is born.

Of course, the issue is that the glue-team that might now have resolved the miscommunication problem between teams a and b has now added yet another team to the org chart. The consequent increase in organisational complexity begets more glue-teams elsewhere, you have glue-teams to link to other glue-teams, the solution makes the problem worse, which leads to even more of the solution.

To avoid this run-away explosion in glue-teams I'd suggest two things. Firstly, the fact that cross-team communication is hard means it should be minimised, organisations should be as modular as possible. This is what bureaucracy originally meant, e.g. the delegation of power to Persian satrapies which meant they could act autonomously. Management schools often teach the reverse, thinking that the way to solve communication failure is to make it a strength by maximising the amount of cross-team communication resulting in endless proliferation of glue people and teams. If your organisation requires good information flow from everywhere to everywhere, it's built to fail.

Secondly, glue should be the last resort. How many communication failures are actually because teams don't have well-defined roles and so things slip through the cracks etc.? How many could be fixed by simple process changes (e.g. monthly catch-ups between related teams)? I'm with Schmidt, the less glue the better.