cage aggression is a myth... and is filled with flawed logic. The last thing you want to do when feeding a snake is pick it up and move it to/from a separate container before feeding...Your chances of getting bit goes through the roof when moving a snake directly after feeding it.
If you think that a snake can't tell the difference between you and a rodent then you aren't giving them enough credit...
Snakes use multiple senses to identify potential prey.
They use their heat pits, their jacobson's organ (smell) and eye sight to ID prey.
So unless you have the same thermal signature, smell like a rodent, and look/ are the same size as a rodent a snake isn't going to think that you are food.
Every major breeder and most of the members on this site including me feed all of their snakes in their enclosures every time without any negative effects.
I'm not saying that you will never get bit... far from it, but when you do it won't be because your snake thinks that you are food.
It is far less stressful for the snake to be fed in it's cage.
IN most cases Spider wobble is very minor and only shows up when the snake is excited/scared/etc. you will notice a slight loss of motor control in the upper neck/head that makes the BP "wobble" In some rare extreme cases they do something called corkscrewing.. this is basically uncontrollable flailing. Once again, this is very rare and not something to be overly worked about. even most of the spiders that corkscrew will still live long happy lives, but in a very small percentage they cannot et very well and do not thrive. All spiders have wobble, and the degree that it presents itself can change throughout the snakes life.