I see your point, but to me its starting to splice hairs because at the time the meta wasn't something that changed much, there was effectively a pre-determined set of actions in the first 10 or so minutes and most matches were less than 16 minutes so perfecting your opening via almost a programmatic efficiency was pretty normal.

The proper inject time (for instance) is just X*N seconds since game start, the second best time is right after that.

Ugh. Why don't the devs randomize things a bit so the game can be more interesting and fun than memorizing digits of pi?

Randomizing doesn't always make games more interesting and fun, it often makes them less skill-rewarding and more frustrating. This especially shows if you play for hours every day.

Generally I would agree, and perfected build orders are part of the reason I stopped watching.