Uses for change-type action?

[Stan Shebs]

Emmanuel Fritsch wrote:
> 
> In fact, I do not understand the specific power of
> change-type action compared to build/garrisoning.

That's a good observation!  In practice, build/garrison
looks weird to players, because both the old and new
units exist at the same time if the construction process
takes longer than a turn, plus which the builder unit
disappears at some time, meaning that if it was the
current unit, some other unit will become the new current
unit.  It will also be described wrongly in notices and
history.

However, these seem more like coding problems rather
than anything fundamental, and it might not be too hard
to add a bit of code to recognize particular types of
builds as upgrades or transformations and handle them
specially.

Stan