I started with 5 normal human-readable JavaScript files - they were around 10 KB in total.
After using YSlow, I decided to merge the 5 files and pack them using Dean Edwards' packer. Now I have 1 file that is 4.5 KB.
When I re-run YSlow, it is now showing the JavaScript file in the primed cache under 'statistics', where previously (when I had the separate files) the 5 files would have been cached.
So I now have 4 fewer HTTP requests but the total page weight for the primed cache is up by 4.5 KB.
Am I doing something wrong?
I am still planning to put a far-forward expiry date header on my JavaScript folder so this issue will likely disappear, but I'm still interested to know why it won't cache the JavaScript files.