> How has this backfired, I'm curious? .. > I'm imagining that the future-you's fail to seamlessly slot-in, and management types don't have an appetite for broken eggs on the way to an omelette, when they already have an omelette in you?

No, not that way - I took about 9 months off in the last 4 years, which has forced a replacement of my past self.

But there are still problems which are "new".

So in a manner of speaking, but more along the lines of filtering out all the easy problems with automation, documentation, others with similar skills - by the time the buck stops at my desk, I have nowhere to move it to.

Instead of being obsolete, I'm a SPOF higher up the problem complexity.

The more guesswork I do, the better I am at guessing what's wrong and every time I pull off a further "last minute miracle", the more entrenched I become, rather than obsolete.

> For me, the anxiety would come from the question "sure, I have this here and now, but would I be able to reproduce this elsewhere, or what this a fluke?"

The success part of it was a total fluke - lots of bets on me by others which came through.