Sure, I have ~/bin and a .emacs.d that I've been working on since last millennium, and various other tools I've written that I use regularly. It's certainly a handicap to work in an environment that's unfamiliar, especially for the first day or two. And sometimes spending five minutes automating something can save you five minutes a day. Making grep output clickable like in Emacs, as demonstrated here, is a good example of that.

But, on the other hand, time spent on sharpening your tools is time not spent using them, or learning how to use them, and the sharpest tools won't cut in the hands of the dullest apprentice. And sometimes spending five hours automating something will save you five seconds a week. All the work I spent customizing window manager settings in the 90s, or improving my Perl development experience early this millennium, produced stuff I don't use now—except for the skills.

> All the work I spent customizing window manager settings in the 90s, or improving my Perl development experience early this millennium, produced stuff I don't use now—except for the skills.

If you enjoyed the process it was time well spent.