[metaphor]

Except they're not. He's using 74161 counters; that's a MSI device, not just primitive combinatorial logic and flip flops.

[tyingq]

Ahh, good catch. I was distracted with the 7400 description. Though a 4 bit counter isn't terribly high level either.

[pas]

Counters are a series of flip-flops anyway, right? And a few latches for reset and load.

https://easyeda.com/normal/74161X2-4qkCwOIZh.png