Regarding the payoff in panel 2 and again in panel 3, I remember when the strip Foxtrot took you to task for only putting in 3 panels and not 4 -as if you were somehow lazy. My response is still the same, you're pretty much the only comic strip cartoonist who puts in 2 jokes in 3 panels. And usually both are funny and could stand on their own. I am majorly impressed that you can keep doing that, considering some of the very lame single payoff panels I see in the dailies, where it might cause a slight upturn of the lip (lately Adam comes to mind) at most.
Also, this strip is the reality of most engineered products. The engineers design them for themselves and other engineers, and when the poor user gets it, he/she has no clue what is going on, or how anything works beyond the simplest task. I know, I worked for 25 years in IT, 13 in engineering test and demonstrated our products at over a dozen trade shows.