Why glow grows?

[JuneTheSecond]

Visio 2013 has addtional effects. Glow is one of them.
When you group a shape that has glow effect, you can add farther glow on previous glow.
Visio 2013 glow is a kind of shape?
Is there hidden master?

Here is a picture of multiplex winding glow in Visio 2013.

[Visio Guy]

I have another glow mystery, maybe it is related.

I was somehow able to get the glow to be around text only. It seems to require a group, but I can't actually create this shape from scratch. I had to go find the old one that I made and re-use it. I couldn't make a new one.

There seems to be some interesting/odd behavior behind glow...

[JuneTheSecond]

Thank you, and also really text can make multiplex glow.