As noted by Robertson and Campanella (1986) “the DMT is extremely simple to operate and to maintain”, while, according to ASTM D 6635 “DMT results are exceptionally reproducible and operator insensitive”. However, when testing semiliquid soils, if highly accurate results have to be obtained, the test procedure must be followed scrupulously. Small errors, unimportant in medium to hard soils, become important when the readings are small. It is advisable to have the tests executed by an operator already familiar with DMT.
A detailed treatment of the topic can be found in DMT execution in semiliquid soils.