Back up ~28yrs. I pull up to my buddy's house and see his dad inside the Scirocco, cranking the engine, and my buddy shooting ether into the intake. I screamed "STOP!". Then, I explained why one never shoots ether into a gas engine. I pulled the plugs, to air out the engine, and determined we had no spark.
Fast forward, to ~2yrs ago. I get a phone call from my buddy saying he'd done something really stupid. "Oh yeah, what was that?", I ask. He says, "I shot ether into my van's intake and it backfired.". "What did I tell you how many years ago?", I asked. He says it wouldn't start and had to use the van. I went through the same reasons why to never use ether on a gas engine. Unfortunately for him, I was working on the road and couldn't work on it. As it turns out, the fuel pump was bad and he blew out the intake gaskets.
A couple months ago, he was going down the highway and the van dropped a cylinder and started making a bunch of racket that sounded like a collapsed lifter. "No problem", I thought, as I've got time to work on it. When I pulled the intake, I found bent pushrods. Not only did the ether blow the intake gaskets, but, it bent pushrods. I took the pushrods to the owner of the shop and explained to him there's no way his no-longer-employed-there mechanic should've missed them, as they were the first thing I saw when the intake came off. Moral of this story: Never ever use ether on a gas engine. If it has compression, fuel, and spark, it'll start.
The grooves in the pushrods are from them rubbing on the passageways through the heads.
I found the lower half of this pushrod lying on top of the cam's distributor drive gear.