I can't really speak to why the rails core team made this default, I think it's a step backwards.
"It's cool." Seriously though, they probably picked it because it requires no configuration. It also avoids hitting the database for things like "Logged in as jrockway", which is always a good thing.
"It's cool." Seriously though, they probably picked it because it requires no configuration. It also avoids hitting the database for things like "Logged in as jrockway", which is always a good thing.