CI + adwords == double-loaded page?

I've been fighting my application for the last couple of days trying to figure out why my sign up page was being loaded twice and causing two sign up emails to be sent to new users.

This only happened on my live site.

After much thrashing and googling I finally downloaded my logs and went looking for missing resources.  After fixing those I still had the problem where the page was loading twice.

Another look in the logs showed me:

[myip] - - [30/Mar/2016:18:40:01 -0400] "POST /account/sign_up HTTP/1.1" 303 0 "https://danceminder.com/account/sign_up" "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.87 Safari/537.36"
[myip] - - [30/Mar/2016:18:40:02 -0400] "GET /account/sign_up_send?id=num HTTP/1.1" 200 2914 "https://danceminder.com/account/sign_up" "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.87 Safari/537.36"
66.249.89.6 - - [30/Mar/2016:18:40:03 -0400] "GET /account/sign_up_send?id=num HTTP/1.1" 200 2914 "-" "Mediapartners-Google"
66.249.89.9 - - [30/Mar/2016:18:40:04 -0400] "GET /account/sign_up_send?id=num HTTP/1.1" 200 2913 "-" "Mediapartners-Google"
[myip] - - [30/Mar/2016:18:40:41 -0400] "GET /account/sign_in HTTP/1.1" 200 3750 "https://danceminder.com/account/sign_up_send?id=num" "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.87 Safari/537.36"
[myip] - - [30/Mar/2016:18:40:44 -0400] "POST /account/sign_in HTTP/1.1" 303 0 "https://danceminder.com/account/sign_in" "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.87 Safari/537.36"
[myip] - - [30/Mar/2016:18:40:44 -0400] "GET /account/sign_up HTTP/1.1" 307 0 "https://danceminder.com/account/sign_in" "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.87 Safari/537.36"


Google was fetching my page and triggering my email logic.

Disabling ads on these pages "fixed" the problem for now.  I never saw this in local testing because I ordinarily run with ads off with my test server.

Anyone else seen this kind of behavior before?