There's no uncertainty here. Every day I ask myself how long something I did would have taken without it. The answer is always crystal clear. It's not hard or difficult at all.

Those studies have well known flaws. I'm measuring my output so I happen to know I'm not only going faster, but the quality is better.

I'm not vibe-measuring my output ;)

studies suggest nothing. i've released a massive number of features in the last year for several projects that i estimate would have taken me multiple years to put together in a much more mentally exhausting way.