Sure, we are all testers. Even with the resources that Canon has, it is not possible to test all combinations, all possibilities, all firmware setting, all shooting situations. How many combinations can you imagine up?
This is not just Canon having a problem - everyone in the electronics/software businesses (and since cameras went digital, they're practically a computer) has this. And then think of the guys who have to test for interoperability with other vendors, whose products have idiosyncratic bugs but YOU have to work around, 'cause "they are big guys, so your design must be wrong".
You know I don't really disagree with any of the responses to this post. My only intent of the post was to find out if anyone else was seeing the sleep issue I've seen. If enough people were seeing it we could then make it known to Canon and ask for a fix.
This is from my last E-mail correspondance with Canon today:
"We appreciate your continued correspondence regarding your EOS-1D X, Extender EF 1.4x III and EF 180mm f/3.5L Macro USM lens.
Thank you very much for the very detailed information. This is extremely helpful to us. I have forwarded this information along to the appropriate party to have this looked into. Again, thank you for taking the time to conduct these detailed tests.
Please let us know if we can be of any further assistance with your EOS-1D X, Extender EF 1.4x III and EF 180mm f/3.5L Macro USM lens. Thank you for choosing Canon."
So, it does appear they are listening. Let's see what transpires.
I wouldn't wait for a solution in the nearest month after they spotted the issue. To apply the fix the whole round of checks should be repeated again and it usually takes a lot of time.