In Section 2.6 of "A Single-Supply Op-Amp Circuit Collection", it says "However, this topology is not recommended because the first op amp is operated at less than unity gain, so it may be unstable."

But:

  • It looks like both of the op-amps are in a non-inverting configuration, so the gain of each has to be at least unity, right?
  • In "Don't fall in love with one type of instrumentation amp", it recommends the two op-amp configuration in some applications for several reasons, and says it's used inside TI parts.

This configuration is also used in split-supply high-gain bioelectric amplifiers:

Amplifiers for bioelectric events: a design with a minimal number of parts

They replace the tail-end resistor with an R and C in parallel to reduce the CMRR problem at high frequencies.

So why is it not recommended?