Driving a DIDW Forward-Curved Exhaust Blower with Two Drive Motors

I am in HVAC field since 1969, started to work as an Erection Engineer and handling design, selection of equipments, costing and execution of Projects of multi million US $ but have never come across a single design/installation in which one DIDW Centrifugal Kitchen exhaust fan is being driven by 2 motors at the drive end of the bloer symelteniously! I had an oppertunity to see such an installation in one of the Military Kitchen Exhaust in Afghanistan. It was an installation by one of the fortune 500 companies in the world. The original installation was not adequate to exhaust the smoke from the wood fired ovens of the kitchen through the chimmney and the entire 200 people dinning areas and kitchen walls and roof were blackned by the soots and smokes. The original equipment supplier and the Army engineers inspite of their sincer efforts over 6 months could not solve the problem. A mechanical engineer with no knowledge of HVAC solved the problem. 1st he increased the two groove drive pulley size to increase the static pressure, modified chimmey out let duct size and found the motor was not capable of handling the additional load. He then changed both the drive and fan pullies from 2 grooves too 4 grooves. Installed an additional drive motor of similar KW of the existing one on the right side of the blower shaft making one motor on right side and one on left side on the drive end aligning the respective drive v belts properly and synchronising the rotations. When the installation was tested, the problem was solved. The Engineer was awarded a Gold Medel by the Army core of Engineers, which was the 1st ever awarded by army to a civilian. Unfortunately I missed to have the installation photographed to show here. Engineers of OEM, Army Head quaters and from other Army Garissons came to study and see how the problem was solved so that they can also follow the same. Have you ever come across any such thing?