I know precious little about tier 1 stuff but this doesn't necessarily sound like a problem in *SE's* network. I wouldn't rule out an error in routes they've contracted with a tier 2 carrier, but since 130ms of the 150ms lag you're experiencing is so close to home, it's likely that addressing that will address the symptoms of the problem you're seeing. It would be interesting if after solving the lag issue your packets still navigated the globe... but it's good for them to get some exercise in so long as it's not hurting anybody.