DNS Lookup times

re: http://www.webpagetest.org/result/141126_CJ_7b1317e60309008d172ff4436ddfe531/

Trying to speedup times from Shanghai, and over many tests I’ve seen wildly different DNS lookup times for our domain xjobs.brassring.com. We discovered that the TTL for our CNAME record was set to zero, causing lookups to go to our authoritative DNS server in the US every time. We fixed that, changed it to 3600, but our DNS lookup times are still long and fluctuate wildly from China.
Does WPT bypass DNS lookup caches and always go to the authoritative server? If so, is there a way to know the DNS lookup times that a user is actually experiencing? If WPT is not bypasing the DNS lookup cache, why are the lookup times so long and varied?

Feature requests: detect & warn about DNS TTLs set to zero, and if it’s not possible today, add an option to honor & use cached DNS entries.