I thought the cage was the cuboid bit with the spring inside, if so then surely that is no more or less vulnerable whether it is the short or long version?as ayceejay said above longer cages are more vulnerable in a accident; also, it’s possible that a short cage would be stiffer and hence may get a more positive shift and potentially lighter in weight.
I have a long cage on my roadie. The rear mech was kaput when I bought it and I had an idea I was going to put a more easygoing cassette range on it next payday for my knees, so went long in anticipation. Found I was happy enough with the road ratio's tho so never bothered with the cassette change.
|U||Ridgeback day 00, back derailluer cable||Bicycle Mechanics & Repairs||21|
|WTD: steel, Ti or Al classic bottle cages||Wanted||13|
|King Cage or similar||Components, Accessories & Clothing||6|
|A||Tiagra front derailleur, Tiagra rear derailleur 10 speed medium cage||For Sale & Auction||6|