If it is a dual CPU Mac Pro they are not officially supported in ESO Mac client currently as noted in the Mac Known Issues sticky here.Everytime there is a patch, large or small. The Launcher will produce Access Denied Error and need to Repair which result in download the entire game all over and verify. That will take a good 4-8 hours. This getting tiresome.
Running 10.9.3, 32GB RAM, Mac Pro Early 2009.
Sometimes the connection is slow though it tends to pick up after an Update has been posted for some hours.I will try with new admin account to apply the patch and see what happen. Then will try to have a clean new install.
With last week's major patch, during the peak hours (early evening PST time zone), the download speed was horrible, from 6-10pm, download speed was around 100kb/s and it ramped back up after midnight. I started the patch download around 8pm and didn't finish the entire patch until around 2am in the morning. During that time, I ran speed test on my connection and was still around 30-40Mb/s.
It's a shared internet but there is no restriction.