Now you have me thinking back to the big(-ish) companies I've worked for. One in particular was a global patchwork of smaller firms, assembled through acquisition. They were never integrated together all that tightly, though. They shared a C-office, a board, and a logo, and not much else. Working with other arms of the company was a lot like working with an outside firm, except everything was priced at cost and you got priority over truly-external clients.

This probably sounds woefully inefficient to the average American business mind, but it seemed to work great. Each sub-firm had their own way of doing things that was tailored to maximize efficiency on a local level. Sure, inter-division communication could be wonky sometimes, but eventually you learn how to iron out those wrinkles.

Sure, there's redundancy in some parts of the business. Those costs are easy to calculate. What's much harder to calculate is the cost of taking 14 manufacturing firms scattered 4 continents, stripping them of their current internal processes, and replacing them with a unified system.