Question to A/C experts (or any one else)

[pmckechnie]

I work on A/C systems every day but mostly on Domestic cars. Ford and GM both place the expansion tube (they don't use expansion valves like MB) at or close to the output of the condensor, rather than at the input to the evaborator. This puts several feet of cold tubing under the hood. It works fine that way, but now the question. WHY would they do this? What are the advantages? I have ask several A/C people about this and none can give any help. They just get this blank look on their face and say nothing.
Got any ideas?