If signs are optional then complying with them should also be optional. This is a case of “we can make laws and tell you about them only after you fall foul of them” Seems like economy has overcome fairness. If a sign is on the other side of the road it can be obscured by any large vehicle, then without repeater signs a driver is not aware of the speed limit and would assume 30mph in a built up area. Another Cash Cow in the making….?