Why is there a delay on my routes loading?

If you go to my app riustats.com and click on the episodes on the left you’ll notice an obviously lag between clicking the item and the URL changing/route starting to load. These links are just normal links using:

<a href="{{pathFor 'episode'}}">...</a>

I have no idea where to begin in debugging this lag, I’ve tried using the ddp-analyzer-proxy and there are no ddp messages sent or received during that lag so I feel the lag is client side but I have no idea where.

Note there is also this delay when loading the routes via Router.go()