Hi Sam.
Thanks for reaching out to us about your issue. We pay special attention to load speeds of our tools. We understand that’s important to you. It’s important to us, too.
I’ve taken a look at your report from pingdom.com as well as the request timeline for your homepage with Chrome’s Developer Tools. The long green receive bar from pingdom.com appears to be a bug on their part. Our script addthis_widget.js is being loaded on your page twice (this is normal — the second time it’s loaded from the browsers cache and doesn’t use a new connection). It looks like pingdom.com is reusing the timing from the first request and incorrectly reporting that the start of the receive from the first request is the same as the start of retrieve for the second.
I put together some screenshots to illustrate.
Here is a marked up screenshot of the pingdom.com report. The purple arrows point at requests added by the plugin. The blue arrow points at the size of the second request (0 B — this indicates it’s coming from cache). Lastly, the green line illustrates that the all but the last color of the time bar line up for the first two requests. They can’t happen at the same time. The first one has to load completely before it can create an environment where it needs to ask for itself again.
Here’s a marked up screenshot from Chrome’s Developer tools. Again, the purple arrows point at the requests added by the plugin. The blue arrows point to the cache indicator and overall time of the second addthis_widget.js request. In this screenshot, you can see the that timelines for the addthis_widget.js requests are completely disjoint.
Thanks,
Julka