Rails is bit like a dirty old man.
Consider this example
class User after_save :do_something_expensive end
Rails makes it trivial to update timestamps, and I found out the hard way that the underlying implementation leaves a lot to be desired.
Easy, right? But, did you know that this useful little method will fire all of your after_save callbacks? This led to some nasty performance problems recently, and now you can now stop Rails from having it's way with you! Bad Touch Rails!
The good_touch project is now available on github and gemcutter and eliminates the overhead for updating a simple timestamp attribute. It's as easy as using the standard/bad touch method without all the horseplay.
Let the touching continue...