[Dune] unwanted refinement with ALUGRID_CUBE

[Matteo Semplice]

Dear Dune,
     I am trying to create on purpose an irregular quad-based grid for a 
test.
My purpose is to have some elements whose neighbours along an edge have 
two different sizes (e.g. one of size 1/2 and two of size 1/4) like this

|-------|  edge of big quad
|-|-|---|  edges of neighbouring quads

Is there something in ALUgrid or DUNE that prevents this?

Here's my experiment.

I start with a grid of a single square (level 0)
I refine it once obtaining 4 level 1 quads.
I mark the north-east and south-west quads and call adapt and I have a 
grid with 2 level 1 quads and 8 level 2 quads.
I do this once more: mark the north-east and south-west level 2 quads 
and call adapt.
This time the level2 quads that were marked get refined, but also the 
level 1 quads (not marked!) are refined.

I am wondering if ALUGRID or DUNE have some mechanism that automatically 
causes the refinement of the unmarked level1 quads. If so, I appreciate 
that this feature is quite understandable (and desirable!) for 
production code, but is there a way to turn this feature off for a test?

Best regards,
     Matteo

-- 
Matteo Semplice			Dip. di Matematica
Phone: 011-			Università degli Studi di Torino
Skype: matteosemplice		Via Carlo Alberto, 10 - Torino