You are getting into a metaphor I saw here on HN some years back: "The Paint Drip" model of skilling. The more you paint over a spot, the more it drips as pai

You are getting into a metaphor I saw here on HN some years back: "The Paint Drip" model of skilling. The more you paint over a spot, the more it drips as paint accumulates. The things you spend the most time on, have the longest drips. Some may be in a T-shape, but as you say, there may be many longish drips in a person's skillset. For the first 10 years of my career, I was more T-shaped. But also pretty good at jumping in and figuring things out. I'm now a lot more "generalist" - I just tell people, "Try me; who knows what I'll know or be able to figure out". I still have some of those really long drips in my paint drip chart, a few really really long, but the nature of tech means that at some point, some tech you learned really well is dead and you'll never need to use it again. Such is life!