Original sentence: Markiewicz and his team used microdiffusion techniques to test for cyanide in samples from the purported gas chambers, from delousing chambers, and from control areas elsewhere within Auschwitz.The amount of cyanide found had a great variability, (possibly due to 50 years of exposure to the elements to varying degrees), but even so, the categorical results were that cyanide was found where expected, i.the control samples
Edited sentence: Markiewicz and his team therefore used microdiffusion techniques to test for cyanide in samples from the purported gas chambers, from delousing chambers, and from control areas elsewhere within Auschwitz.The amount of cyanide found had a great variability, (presumably due to 50 years of exposure to the elements to varying degrees), but even so, the categorical results were that cyanide was found where expected, i.Therefore, since cyanide residue was found in the chambers in question, the test would confirm that they were in fact gas chambers, not mere residential rooms as was the alternative hypothesis or morgues, as has been suggested by revisionist readers of Auschwitz architectural and engineering documents.the control samples, validating the reliability of the test with both positive and negative controls