Trying to get page-load time down.
I followed the third example outlined here to asynchronously load the TypeKit javascript.
To make it work you have to add a .wf-loading #some-element {visibility: hidden;} to each element that uses the font, and after either 1) it loads or 2) after a set time (1 sec), the font becomes visible.
The thing is, the CSS I'm working with has the font assigned to about 200 elements, so thats 200 elements of .wf-loading{ } (note: I did not write this CSS).
I feel this would slow the load time down more than just letting it load regularly, DOM traversing that much stuff. If this is the case, I will just axe Typekit altogether and go with a regular font.
Are there any tools I can use to run performance tests on this kind of stuff? Or has anyone tested these things out?
You're not actually modifying more than a single DOM element (the root ) with this approach. This means that our modern browsers will rely on their super fast CSS engines, so the number of elements involved will have no noticeable affect on page load.
As far as page load and flicker, network latency is usually an order of magnitude worse than DOM manipulation. There will always be some flicker on the very first (unprimed) page load while the browser waits for the font to download. Just make sure your font being cached for reuse, and try to keep it's file size as small as possible.
I went down this path a few years ago with Cufon. In the end, I chose the simplest path with acceptable performance and stopped there. It's easy to get caught up in optimizing page loads, but there's probably more promising areas for improvement – features, bugs, refactoring, etc.