diff --git a/data/water.gro b/data/water.gro
new file mode 100644
index 0000000000000000000000000000000000000000..147f5680a2576c10a23853e014af36af525102f4
--- /dev/null
+++ b/data/water.gro
@@ -0,0 +1,403 @@
+WATER
+  400
+    1W        W    1   0.084   3.595   3.359  0.0663  0.0148  0.2032
+    2W        W    2   0.460   2.488   2.882  0.0999 -0.0648 -0.1661
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+  370W        W  370   3.573   0.024   1.141 -0.1586  0.1127 -0.2725
+  371W        W  371   1.261   1.659   0.304  0.4082 -0.1876  0.1785
+  372W        W  372   3.427   0.996   1.294  0.0834 -0.0538  0.4157
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+  374W        W  374   3.055   2.366   2.919 -0.0247 -0.2816 -0.3012
+  375W        W  375   2.709   3.067   0.386 -0.1355 -0.1989 -0.2566
+  376W        W  376   1.324   0.742   3.292  0.0955 -0.0797  0.5514
+  377W        W  377   1.144   1.326   2.533 -0.0683  0.0474 -0.2325
+  378W        W  378   3.236   2.821   2.810 -0.3311 -0.0287 -0.2906
+  379W        W  379   2.336   0.771   3.187  0.1146  0.0371 -0.2916
+  380W        W  380   0.180   1.242   2.964 -0.0441 -0.1830 -0.1295
+  381W        W  381   1.940   1.719   2.690 -0.0144  0.0463 -0.1025
+  382W        W  382   0.297   2.477   1.347  0.0757 -0.0251 -0.1316
+  383W        W  383   0.444   1.774   2.237 -0.0694 -0.3087  0.0707
+  384W        W  384   2.761   2.060   2.587  0.3107  0.2012 -0.0691
+  385W        W  385   2.533   3.440   3.398 -0.0317 -0.1247 -0.1516
+  386W        W  386   2.429   1.179   2.951 -0.1043  0.1520 -0.1340
+  387W        W  387   2.706   3.233   1.356  0.0570  0.4550 -0.0556
+  388W        W  388   1.708   2.953   2.679  0.3637  0.0704  0.0366
+  389W        W  389   1.193   3.308   1.948 -0.0395  0.0042 -0.0031
+  390W        W  390   2.998   2.479   2.367  0.3160 -0.0373  0.0552
+  391W        W  391   2.048   2.551   3.504 -0.0849 -0.0297  0.1256
+  392W        W  392   0.653   2.504   1.843  0.0882 -0.0692 -0.2940
+  393W        W  393   2.999   2.263   1.488  0.1866  0.3055  0.3291
+  394W        W  394   2.640   3.329   2.239  0.2390  0.1363 -0.0792
+  395W        W  395   0.618   3.058   2.109 -0.0167 -0.0406 -0.0423
+  396W        W  396   1.639   1.110   3.319  0.0300 -0.3053  0.0710
+  397W        W  397   2.090   3.276   0.830 -0.0307  0.0044  0.1215
+  398W        W  398   1.398   2.531   3.468  0.0631 -0.0196 -0.4235
+  399W        W  399   1.524   2.769   0.845 -0.5337  0.0559  0.0075
+  400W        W  400   0.745   1.509   0.104  0.1616 -0.0161  0.1005
+   3.64428   3.64428   3.64428
diff --git a/doc/source/pycgtool.warnings.rst b/doc/source/pycgtool.warnings.rst
deleted file mode 100644
index cc5e32b5c3eb729415e0ed659dd37785f6ed0895..0000000000000000000000000000000000000000
--- a/doc/source/pycgtool.warnings.rst
+++ /dev/null
@@ -1,7 +0,0 @@
-pycgtool.warnings module
-========================
-
-.. automodule:: pycgtool.warnings
-    :members:
-    :undoc-members:
-    :show-inheritance:
diff --git a/doc/source/tutorial.rst b/doc/source/tutorial.rst
index 72e05a19881ab2a965d9c5ab2d3d311009c717f3..c7f83e10963e94b57387d83472c271e4c70ce9fd 100644
--- a/doc/source/tutorial.rst
+++ b/doc/source/tutorial.rst
@@ -132,3 +132,17 @@ These samples were compared in the paper using an R script to generate a series
 If the automatically generated parameters provide an accurate representation of the reference structure, the percentage error between the two samples will be small.
 
 Validation of the more general molecular conformation may be performed by comparison of the radius of gyration of the reference and CG models.
+This may be performed using the standard GROMACS too `gmx gyrate`::
+
+    gmx gyrate -f ref.xtc -s ref-for-rgyr.tpr -o ref-gyr.xvg
+    gmx gyrate -f md.xtc -s md.tpr -o cg-gyr.xvg
+
+These commands will calculate the radius of gyration for each trajectory frame for both the reference and CG simulations.
+The resulting `.xvg` files may be visualised using a graphing program such as `xmgrace` or compared in the same way as the bonded samples, using::
+
+    average_columns.py ref-gyr.xvg cg-gyr.xvg
+
+As before, a small percentage difference in each of the columns suggests good replication of gross conformation.
+
+In addition to these simple forms of validation, it is recommended that further validation, relevant to the class of molecule, is performed.
+In the case of membane lipids, for instance, this may take the form of an assessment of membrane thickness and surface area per lipid.
diff --git a/doc/tutorial_files/Makefile b/doc/tutorial_files/Makefile
index 27c93ddf91184c9a9645d31f8fb360f266bd6851..35bd7f9b1bff280a3cc536db19ecc05e6a8bb807 100644
--- a/doc/tutorial_files/Makefile
+++ b/doc/tutorial_files/Makefile
@@ -1,4 +1,4 @@
-all: pycgtool cgprepare em npt md
+all: pycgtool cgprepare em npt md samples rgyr
 
 pycgtool:
 	../../pycgtool.py -g ref.gro -x ref.xtc -m atenolol.map -b atenolol.bnd
@@ -20,9 +20,19 @@ md:
 	gmx grompp -f md.mdp -c npt.gro -p topol.top -o md.tpr
 	gmx mdrun -deffnm md -v
 
+samples:
+	../../pycgtool.py -g ref.gro -x ref.xtc -m atenolol.map -b atenolol.bnd --advanced
+	mv {36KB,ref}_length.dat
+	mv {36KB,ref}_angle.dat
+	../../pycgtool.py -g md.gro -x md.xtc -b atenolol.bnd
+
+comparesamples:
+	./average_columns.py ref_length.dat 36KB_length.dat
+	./average_columns.py ref_angle.dat 36KB_angle.dat
+
 rgyr:
-	gmx gyrate -f ref.xtc -s ref.tpr -o ref-gyr.xvg
-	gmx gyrate -f md.xtc -s md.tpr -o cg-gyr.xvg
+	echo 2 | gmx gyrate -f ref.xtc -s ref-for-rgyr.tpr -o ref-gyr.xvg
+	echo 2 | gmx gyrate -f md.xtc -s md.tpr -o cg-gyr.xvg
 
 clean:
 	git clean -i