He may feel some of the unique properties of Glycin are under appreciated
Probably because he seems not particularly aware of the characteristics of HQMS. On the other hand, Glycin seems weird and rare - and was promoted as something to be valued in Ansel Adams's books (which makes it seem to have roughly similar value to a particular type of hobbyist as reliquaries and their contents had to the medieval church).
I have used this one with agitation every 3 minutes [I think this is outside the scope of what Lachlan is referring to].
Unique property is even development with no streaks [better than Rodinal], increase in effective EI and sharpness partly due to adjacency effects. It is however a bit grainy and thus entirely believable that Prescysol EF [formula unknown] might provide the advantages without the grain, as catechol would harden the emulsion and stop the grains getting so big.
Anything other than dead standstill/ zero agitation will really only affect overall density achieved - thus you can get to the same end point simply by adjusting other aspects of process control. So we can eliminate agitation as having any 'improving' effect on sharpness, other than that you should aim to develop to the least necessary highlight density for the grade of paper you are aiming for (don't compromise negs for bad scanners). With extremely highly hardened emulsions, further emulsion tanning is highly unlikely to have meaningful effects on sharpness - whereas emulsion interaction with certain development inhibition agents (either from the developer or via silver-solvent-caused release from the emulsion) will. In other words, it's the Phenidone in the various staining developers in this thread that's doing the heavy lifting sharpness-wise and the HQ or Catechol or Glycin etc are effectively largely acting as electron transfer agents - and that the reason FX-2 may seem reasonably sharp probably has more to do with Glycin's relative lack of effect (compared to HQ/ HQMS) as an electron transfer agent - i.e., compared to FX-1, there's some electron transfer happening thus FX-2 might seem a little 'smoother' tonally - because the Metol exhaustion caused adjacency effects are being somewhat (not totally) diluted - as opposed to HQ, which seems to fully stop the exhaustion effects in MQ formulae. So, with FX-2, you're not going to get anything beneficial at all over something like Perceptol/ Microdol-X at various dilutions - or Beutler. Ilfosol 3 seems to exploit both the emulsion contained inhibition agents and the phenidone development inhibition effect - it's very, very sharp, but with the visual consequences of that in terms of more visible granularity, though without the high frequency loss of information and lack of lower frequency sharpness enhancement that Rodinal suffers from (which does not detract from Rodinal's aesthetic value), or the lack of highlight density control (development inhibition effects again) - in other words, it's an actual high-definition developer that does the job properly because it seems to aim to exploit the combination of development inhibition from both emulsion/ developer solvency interaction
and a developing agent used in a way such that it'll cause development inhibition effects - while having a pH that's dead-on for optimising sharpness (which seems to follow a bell curve plot relative to pH) - most of the developers mentioned in this thread tend to focus obsessively on one or two of these aspects (and usually utterly exclude solvency - suggesting they're stuck somewhere before 1955 in their knowledge) rather than dealing with the need for them to all to be used together.
