Hi Jeff,

A sliding dovetail can indeed be a very strong joint.

Glad to hear it.

Considerations - if the direction of the grain in both pieces is the
same - like almost all the stands in the website you referenced - then
a simple butt joint, long grain to long grain, will be stronger than
the wood itself. This will easily hold up any music book you have. It
takes hundreds or thousands of pounds of force to crack a well made
glue joint.

I guess part of my considerations is when kids play around the platform,
they may knock it flying and it's the sudden G-force that would get
applied to the corners might cause a span

You have to be careful that the dovetail socket is not too close to
the edge of the board. Also, 27" is a fairly long joint, and making
sliding dovetails is not terribly forgiving. How were you going to
accomplish this? Router table? Special jig?

Was planning on using a router table, as per one fo the websites
mentioned by another poster.

A well-fitted sliding dovetail has lots of inherent mechanical
strength, glue is only necessary to keep the joint from sliding apart.
You can slide the joint mostly together dry, and only need to put glue
on the last couple inches.

Ah, good point, hadn't thought if that possibility.
Steve