Tim W writes
Iread in many places about the need to gently introduce seedlings to the
outside. What's the point of this? It sounds like a lot of fuss and bother.

You're taking them from a warm place to where the night time temperature
will drop to a few degrees centigrade. They can adjust, but slowly. If
you don't want the bother you can.
a) put them outside straight away, choosing a time when the weather
forecast for the next few nights is for warm nights - in effect getting
the weather to do the hardening off for you. You will lose quite a few
plants this way when the temperatures dip lower than expected. Rather
than lose a few plants of each batch, you'll basically lose all of the
type of plant that doesn't like that temperature, whereas other less
cold susceptible plants will survive.
b) keep them inside until outside temperatures have caught up - some
time in late May or early June. This works if you have a greenhouse, but
if you try to do it on a windowsill, they won't get enough light and
will grow weak and leggy as they try to accelerate to more light.
--
Kay