Nice Post "Naturalist".
Baby rattlesnakes are only doing what they need to do for protection. As you encountered, in the countless rattlesnake encounters I have had, I have NEVER had one be aggressive, even after having practically stepping on them.
Rarely do you ever hear of anyone dying from a rattlesnake bite. The individual that died after being bit by a rattlesnake in Lytle Creek actually died of a HEART ATTACK! He was responding very well to anti-venom treatment as was expecting to be released shortly.
If you ever are bit by a rattlesnake, NO CUTTING, NO TOURNAQUETS. While there are some good suction devices that will suck much of the venom back through the original puncture wounds (I never hike without it), just remain calm and get help.