Is that a weird use of opamp ?

[seanny]

Here is another example

http://www.sonicimagerylabs.com/pro...nh_Ticha_Docs/990Enh_Ticha_AppNote10_RevA.pdf

 

[forr]

I guess the Alexander current feedback power amp uses the similar idea.
https://www.analog.com/media/en/tec...tes/58052492001115525484056221917334AN211.pdf

The Mark Alexander's patent US 5 097 223 is dated Mar.17, 1992.
Siliconic's schematics was published in 1985
in "Mospower Applications", page 6-125 :
1985_Siliconix_MOSPOWER_Applications 1985 Siliconix MOSPOWER Applications

 

[stanislav1957]

The amplifier is class B. the Author Е.Гумеля. My version.The model and diagram are attached.