It looks for me that despite what author wrote, he WAS indeed in exploratory phase: `So now we have a sequencer device, how do we get events from it? Can we do it in the main loop? Turns out it probably doesn't integrate too well with Qt, (...)`

`My initial thought was making a grid of spinners,(...) but then I realized that there isn't an easy way to make headlines in Qt's grid. (...) So after some searching, I found out that it would be better to have a tree view(...)`

And many similar things. Exploration and technical spikes - nothing wrong with that but author wrote: ` It's pretty common to do so if you're in an exploratory phase, but in this case, I had a pretty good idea of what I wanted to do right from the start, and that plan seemed to work. `

and then he contradicted himself writing about various difficulties and explorations... (I don't see anything wrong with that, absolutely. I think that exploratory phase is essential to good design).