How do I install a water line for a refrigerator in a galley kitchen?
Sure, the water is under pressure, it'll get there. As far as static pressure loss, the entrance and exit are all that matter, the in between makes no difference. Friction loss is an issue with long distances, but ice makers and dispensers have very low demand, so unless your house pressure is very low already, it shouldn't be an issue. The only real drawback would be the appearance if you have no convenient ways to disguise the run.