Mechanical Specific Energy (MSE) is now a well-known concept to quantify the cutting efficiency of the rock. Thanks to its simplicity, its utilization has significantly increased over the last few years with electronic drilling recorders, especially in unconventional wells to optimize the drilling process and eventually reduce cost. A typical use is to compare the MSE to the rock strength to see whether the right amount of energy is utilized at the bit and not wasted or dispersed...