In message , "tim (moved to sweden)"
writes

Perhaps they can for a short stretch of track, but I don't think
that I've ever seen anything close to this on the whole length of
a single line. Anything more than one tram about every 2 minutes
causes bunching at traffic lights [1] and stops.

The Cross River Transit tramway plans for a 90-second headway through
the central section. On most modern tram systems, the approach of a tram
will clear traffic lights in its favour, so these rarely cause delays -
stops do, of course.

This bunching clears when separate routes diverge,

Indeed - CRT has two branches north and two branches south, so 90
seconds may be realistic.

but if they all go to the same place the service become unworkable at
this frequency.

I've certainly seen trams running at something like a 40-second headway
in parts of Prague - but I've also been stuck in some ginormous
tram-jams in that city, too!

--
Paul Terry