I'm new to watching the tour and its rules/strategy. how does it help a leader if a fellow team member "chases" a breakaway rider? Say Armstrong's in the lead and sends his domestique (I like that) to "chase" a breakaway rider: how does that help Armstrong? Doesn't he himself have to catch up to prevent Mr. Breakaway from eating into his lead? Is it because the team member will draft him up to the breakaway?