So a 70 year old Grandpa and a 68 year old Grandma

A 45 year old and 61 year old man show up on a heavy industrial site to build some very heavy structure. The site management thinks the crew is a joke and tries a few times to get it removed from the job. The 4 keep their head down and keep using the techniques developed by the Grandpa. As the job nears completion the site management is amazed at the precision of the structure even though the crew ignored all the suggestions of the management. There were a few changes and unannounced modifications. The crew over came all the obstacles and finished the job in 1/2 the time that was expected of the healthy young crew the management wanted. I guess experience does count for something after all