Heating pipe buried in wall correctly?

[kasser]

Came across this today.
Plastic central heating pipe directly buried in wall.
Wall to be plastered soon.
Isn't the plaster going to crack as soon as the pipe expands? Especially plastic?

If you run pipe in pipe, I've always wondered how you clip/hold the pipe inside? It's just not possible?

 

[ShaunCorbs]

I would use hair felt insulation

As for clips either nail ons or p clips