I've been doing the JoAT thing pretty much my whole career and yes, there have been companies that would refuse to hire me because of not being the "master of one" person. It could be tough.
My answer to that is to find a companies that actually need JoAT roles and it seems to have worked so far. But I must add that the older I get the more I tend to try to settle on a concrete direction, so I guess age may also be a factor.
I like this idea of finding a company that suits you as well as the company looking for me to suit them. It implies a really nice, mutually beneficial relationship which all employees should aspire to have at work. :) But you're also right, it must be nice to settle eventually into a role you know has progression and is a passion for you.
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