Super fast socks

It's 9:30 am Wednesday morning and I already have half a sock! I finished turning the heel on the bus this morning. I started these slipper socks Monday night with lots of guidance from Cassandra. Another intense knitting session last night, and I was almost finished wtih the heel. Now I can knit the ribbed cuff on my bus ride home tonight, and maybe knit the second sock toe tonight while watching TV.

Why don't normal socks work up this fast?