Trackless trams or in reality autonomous guided buses with tram like features should not be used if there is sufficient demand on a route to support a tram as trams will have a lower overall cost, support high frequencies,
and have the potential for urban regeneration. New developments of low mass trams ULR (Ultra Light Rail) e.g. Trampower Cityclass, Coventry VLR (Very Light Rail) and prefabricated trackforms Trampower LR55, Coventry trackform offer lower costs.

The Department of Transport will fund tram projects but it requires political commitment, numerous studies to assess viability, routes, underground services. etc.
Any new major service must have an integrated transport plan that deals with cars, car parking, bicycle and walking, tram, trains and buses interaction/ nodal hubs, rat running, speed, land use planning, etc.

Guided buses
– autonomous control of any vehicle (tram, car, truck…) on public roads is not currently regulated
– autonomous control on public roads is still a work in progress (the accident rate is higher than car drivers but the injuries minor https://caraccidentattorney.com/blog/self-driving-car-accident-statistics/ )
– steel wheels on rails are ~3 x more energy efficient
– rubber tyres produce particulate air/water pollution
– as it tracks a similar line road damage to bitumen is higher and
– at platforms it tracks the exact same line so a reinforced road base is required
– the ride is as good as the buses suspension (some are much better see CRCC) and road surface maintenance
– optical systems can be obscured … snow, mud, fog  though electronic embedded ones are now used by some manufacturers
– they have not been shown to have significant modal shift (ie attracting car drivers) whereas trams have ~30% thus freeing up road space
– the lack of a fixed unchangeable  route gives developers less confidence to invest in regeneration