A big part of my job is traveling the world talking about the consumerization of IT, and one of the most common challenges I hear from people is that they have a hard time convincing the higher ups and their companies that consumerization is real and something they have to deal with.
This makes sense considering one of the major tenets of consumerization is that most of what you're doing in IT today won't work moving forward, and you're going to have to make a lot of changes. This means the unfortunate reality is that it's much easier for companies to deny or ignore the issue of consumerization rather than digging deep and making fundamental changes to how IT services are delivered.
So how to you convince the powers at your company that this is something real? Simple. You have to start keeping a list of all the actual real-world things that are happening in your company where users are doing whatever they want to get around IT. I call it the "FUIT Book of Anecdotes."
You can use the FUIT tag on BrianMadden.com to read some articles which might make great starting points for your documentation, (including using a MiFi or changing ports to get around network restrictions, setting up powerline networking to get around firewalls and security systems, and using simple printer test pages to get around complex network access protection).
I can't claim credit for the original idea for a book like this. Credit is due to Jeroen van de Kamp and his team of consultants who presented it at a conference I attended recently. But I love the concept! Document as much as you can to prove that your current IT systems, processes, and hardware are not as secure or compliant as you think they are, and then build your plan to replace them.