Originally Posted by
slcbob
Not in my experience or in theory -- the weight up high on your back (backpack, messenger bag) is LESS stable, due to higher COG and less rigid attachment.
Concur bunny hopping is much harder with panniers. Bunny hopping moves the bike relative to the rider, and the more weight directly attached to the bike rather than "sprung" through your body, the harder it is.
A lower COG might make it harder for somebody to knock you over but for me at least that's not how winter crashes happen (winter is when I'm most concerned about crashing).
When I've crashed it's because the bike has slid completely out from under me or because I couldn't correct a front wheel skid. Having the weight on my body vs on the bike has helped me recover from skids or prevent them in the first place because I have more control over where the weight is at any given moment. Wearing a backpack or messenger bag doesn't necessarily mean that you've got stuff flopping all over either.