yes, and surge is the act of moving faster and her concerns were with the runescape engine. I'm no software engineer but I don't see why there would be a different amount of load on the engine with someone running the same speed as surge.
Surge likely teleports you to X coordinates, though - hence why "Destination unreachable", and thus different to run being sped up.
That being said, Run/walk are probably set to 2/1 tiles respectively because RS is too small for anything higher to be viable. Look at NXT for a similar example of how small RS actually is.
Unslain Bosses - Clan