Note: both sites focus on loudspeaker amps. But line-level op-amps use similar techniques. Generally you can omit one stage of output buffering when loads are always way above 8Ω. Omitting the big-fat output transistors may allow more GBW. (OTOH, speaker amps generally run at gain of 20, general purpose op-amps often are compensated for unity gain.) And of course voltages are high in high-power loudspeaker amps.
If you take Self's basic plan, reverse polarity (his inputs are PNP not NPN), and lose the big output devices, it is essentially the same as a Jensen 990 in general layout. There are many-many small differences: Self is a simplifier and Deane was a tweaker. Comparison of the two approaches might be illuminating.