diff --git a/benchmarks/extrude/t1_boundary_layer.geo b/benchmarks/extrude/t1_boundary_layer.geo
index 6121adb6aa4eace865791c7ec677c281fbbcdf35..9e316c530f2991a53f69fd71764429f472fc0c70 100644
--- a/benchmarks/extrude/t1_boundary_layer.geo
+++ b/benchmarks/extrude/t1_boundary_layer.geo
@@ -1,91 +1,23 @@
-/********************************************************************* 
- *
- *  Gmsh tutorial 1
- * 
- *  Variables, elementary entities (points, lines, surfaces), physical
- *  entities (points, lines, surfaces)
- *
- *********************************************************************/
-
-// The simplest construction in Gmsh's scripting language is the
-// `affectation'. The following command defines a new variable `lc':
-
-lc = 0.009;
-
-// This variable can then be used in the definition of Gmsh's simplest
-// `elementary entity', a `Point'. A Point is defined by a list of
-// four numbers: three coordinates (X, Y and Z), and a characteristic
-// length (lc) that sets the target element size at the point:
-
+lc = 0.05;
 Point(1) = {0, 0, 0, lc};
-
-// The distribution of the mesh element sizes is then obtained by
-// interpolation of these characteristic lengths throughout the
-// geometry. Another method to specify characteristic lengths is to
-// use a background mesh (see `t7.geo' and `bgmesh.pos').
-
-// We can then define some additional points as well as our first
-// curve.  Curves are Gmsh's second type of elementery entities, and,
-// amongst curves, straight lines are the simplest. A straight line is
-// defined by a list of point numbers. In the commands below, for
-// example, the line 1 starts at point 1 and ends at point 2:
-
 Point(2) = {.1, 0,  0, lc} ;
 Point(3) = {.1, .3, 0, lc} ;
 Point(4) = {0,  .3, 0, lc} ;
+Point(5) = {.1, 0, .2, lc} ;
+Point(6) = {0,  0, .2, lc} ;
 
 Line(1) = {1,2} ;
 Line(2) = {3,2} ;
 Line(3) = {3,4} ;
 Line(4) = {4,1} ;
-
-// The third elementary entity is the surface. In order to define a
-// simple rectangular surface from the four lines defined above, a
-// line loop has first to be defined. A line loop is a list of
-// connected lines, a sign being associated with each line (depending
-// on the orientation of the line):
+Line(5) = {2,5};
+Line(6) = {5,6};
+Line(7) = {6,1};
 
 Line Loop(5) = {4,1,-2,3} ;
-
-// We can then define the surface as a list of line loops (only one
-// here, since there are no holes--see `t4.geo'):
-
 Plane Surface(6) = {5} ;
 
-// At this level, Gmsh knows everything to display the rectangular
-// surface 6 and to mesh it. An optional step is needed if we want to
-// associate specific region numbers to the various elements in the
-// mesh (e.g. to the line segments discretizing lines 1 to 4 or to the
-// triangles discretizing surface 6). This is achieved by the
-// definition of `physical entities'. Physical entities will group
-// elements belonging to several elementary entities by giving them a
-// common number (a region number), and specifying their orientation.
-
-// We can for example group the points 1 and 2 into the physical
-// entity 1:
-
-Physical Point(1) = {1,2} ;
-
-// Consequently, two punctual elements will be saved in the output
-// mesh file, both with the region number 1. The mechanism is
-// identical for line or surface elements:
-
-MyLine = 99;
-Physical Line(MyLine) = {1,2,4} ;
-
-Physical Surface("My fancy surface label") = {6} ;
-
-// All the line elements created during the meshing of lines 1, 2 and
-// 4 will be saved in the output mesh file with the region number 99;
-// and all the triangular elements resulting from the discretization
-// of surface 6 will be given an automatic region number (100,
-// associated with the label "My fancy surface label").
-
-// Note that if no physical entities are defined, then all the
-// elements in the mesh will be saved "as is", with their default
-// orientation.
-
-Extrude {
-  Surface{6}; Layers{5, 0.1}; Recombine;
+Line Loop(7) = - {5,6,7,1};
+Plane Surface(8) = {7};
 
-}
+Extrude { Surface{6,8}; Layers{5, 0.01}; Recombine; }