First, here is a map of the Sydney rail network that may clarify the Lidcombe-Bankstown issue described in Chapter 4. A train departing Sydney’s Central station with destination “Lidcombe” is probably travelling the orange line, which ends at Lidcombe, instead of one of the lines that’s useful for getting from Central to Lidcombe. Lidcombe is a final destination, but the orange line is U-shaped, so what matters at Central is that it goes via Bankstown, not that it ends at Lidcombe. Lidcombe is the “TO” but in this situation, the “VIA” (via Bankstown) matters more.
On the other hand, if you’re considering the orange line from midpoint station such as Marrickville, the “Lidcombe” (TO) matters. At this point, this It’s telling you which branch the orange line will follow when it splits at Birrong. But it’s also telling you, generally, that this train goes westward along the line rather than eastward.
In signage, transit agencies need to think about whether, at a particular station or stop, the TO and VIA matters more — and if both are needed, which should be emphasized. For fixed signage at stations, it’s not hard to adjust the content to say what matters from the perspective of that particular station. If you can’t, do both: “Lidcombe via Bankstown” or even better (at Central) “Bankstown, and on to Lidcombe.” The latter message properly emphasizes the direction of the train from the point of view of Central, while still signaling the onward path. This method is almost never used, but there are many situations where it can be useful.
For signage onboard transit vehicles, the content can now be made responsive to the vehicle’s location, so that signs are automatically updated when the vehicle passes a particular point on the line. That suggests that bus signs could be more frequently updated to present just the information needed at the stops that it’s passing — which could make for much simpler and clearer signs.
Why care about signage? Because clear signage makes the system look simpler, and suggests, more directly, that transit is ready to serve your freedom. And because clarity and accuracy are beautiful.
For a more thorough discussion of the “to-via” problem in the context of Portland and San Francisco, dealing particularly with the pleasures and clarity that arise from naming lines after major streets, see this article.