Rails 4 turbo-link error: Uncaught TypeError: Cannot read property 'position' of null

Rails 4 turbo-link error: Uncaught TypeError: Cannot read property
'position' of null

I'm building a Rails 4 app and I have a few scattered js files that I'm
trying to include "the rails way". I moved jquery plugins into the
/vendor/assets/javascripts and I updated the manifest (application.js) to
require them. When I load the pages locally I see that they appear
correctly.
However, I'm getting inconsistent behavior from one of the scripts that's
compiled. I have a controller-specific js file called projects.js which is
referenced in the application.js via the use of require_tree .:
//= require jquery
//= require jquery_ujs
//= require turbolinks
//= require bootstrap.min
//= require jquery.form.min
//= require_tree .
I see the file is included correctly, and it works... half the time. The
other half of the time, the stuff in projects.js doesn't seem to do
anything (it's mostly jquery animations and some ajax requests). When it
doesn't work, I'll click buttons a couple times, nothing will happen, and
then I'll throw this error:
Uncaught TypeError: Cannot read property 'position' of null
turbolinks.js?body=1:75
This never happened when the scripts were in the individual views (the
wrong way), so I'm fairly certain the problem is not with my javascript
code. One other potentially relevant details is that the stuff in
projects.js is wrapped in a $(document).ready(function(){. Also, I'm
testing in development mode so the javascripts and css are not combined by
the asset pipeline.
Any idea what's going on here? I'm new to Rails but I've done my best to
follow all the conventions.
Update!
It's predictable when my project scripts don't work. The first page load
works every time. Then I click one link to a new page which uses my
project.js behaviors and the second page never works. I click a few times
and eventually throw the error above. I'm still not sure why, but I'm
suspecting this is related to turbo-linking.