I think if someone tries hard enough, they can make anything not outside the realm of reality occur. That being said, short of pumping with an FTP 50+ times rapidly, I think igniting a petroleum-based lube in a typical off-the-shelf pumper, even modified is not too likely.

There are always stories of people having done something- i.e. the melted delrin pistons or igniting a petroleum lube in a pumper- but these are usually at the extreme ends of the concept- i.e. 50 pumps, or 50+ pumps with a metal piston- not where 99.9% of people are going to find themselves generally. If the concept is to "break the box"- this can always be achieved- but should it mean everyone should conduct themselves in a regular day-to-day setting in a manner orienting at addressing a break-the-box scenario? Not really. If someone is going to test "extremes" then I would agree they should use the best materials for the job, but for Joe and Fred who are not attempting to test the extremes, or even come near approaching them, this is not a requirement.

I think what we are having here is a back-forth of "extreme engineering" vs. "common use"- which if we take it too far means no one leaves their house in the morning without putting on an armoured, anti-UV radiation suit.