What use are long feeler gauges?

[Dave Price]

For work I recently acquired some long feeler gauges for poking into joints in building cladding systems. They don't need to be accurate for this just thin and flexible. My question is. What is the true purpose of one foot long (300mm) feeler gauges, as it isn't setting spark plugs. Why would you need massively long feeler gauges?

[Paul Thomas]

to keep your hand away from the oily bits

[Paul Sheridan]

I have foot long feeler gauges that were supplied by Vauxhall for adjusting all of the early bucket type tappets, as they had to be finely adjusted with the engine running. So you didnt want to be getting your fingers in the way! 

Had them in a draw of my tool box for nigh on 40 years now.