Why is there no instrument taxi system for low-visibility operations? In one of the comments on this answer regarding ILS category IIIc operations (or, rather, the lack thereof), it's mentioned that

There is no [radio] guidance for taxiing except the pilot's vision.

And, in an answer to another ILS IIIc question, it is stated:

There is no provision in the ILS system to provide for an auto-taxi or runway vacate. IIIc is just zero-zero and roll-out control, not auto-vacate as the linked AvWeb article seems to suggest. Its a logical extension of the FAA definition, however auto-taxi is not part of the CAT IIIc definition or system requirements. The only requirement is to get the aircraft on the runway and stopped.
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Right now there is no airport approved for IIIc approaches because the aircraft would just sit on the runway, it has no way of taxiing in. Until an augmentation system like GPS with WAAS or LAAS, or the &quot;Ground-Based Augmentation System&quot; is developed further, automatic taxi is not there.
There is no provision in the existing ILS signals that allow for an aircraft to vacate the runway.

Given that the ability to land is meaningless without the ability to taxi off the runway and to the gate (this is why, even though today's airliners are perfectly capable of IIIc landings, there are, in practice, no such landings, as no airport is equipped to taxi an aircraft in from a IIIc landing), why isn't there an &quot;Instrument Taxiing System&quot; to allow zero-visibility taxi?
If I were an airline executive in charge of determining the configuration of new aircraft being ordered from a manufacturer, and one of the options was an instrument taxiing system to allow so-called zero-visibility taxi, the aggregate cost of that system (purchase, maintenance, training, fuel to carry it) would have to be very low before I would consider it. My initial thought would be to reject it out of hand, but perhaps the ability to help a taxiing pilot navigate the taxiways of an unfamiliar airport would bring me around if the only cost was additional software for existing equipment. I say this as a pilot who on his first trip into Chicago O'Hare succeeded in getting some deservedly unkind words from a ground controller when I didn't turn when I should have and necessitated the rerouting of other aircraft.

In 10 years on the 747 I only once called for a follow-me car because of low visibility, and had the taxiway been better marked or my eye level lower I might not have needed that.


  So it wasn't worth it even for airports where crap weather is common?


Consider the Arcata-Eureka Airport in McKinleyville, CA. The airport was deliberately built during World War II where they could depend on it being very foggy, and in that they succeeded. While the approach and landing were often challenging, there was never any real difficulty in taxiing if you were familiar with the airport.