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[802.3af] Another Minor IEEE802.3af D4 issue - use of "PG"

Dear team
Section 33.4.1 (Isolation) refers to "frame ground" and section refers to "protective ground". Are these intended to be the same thing? If so would it be best to use a single term? (I hope this isn't opening a can of worms - the existing IEEE802.3 also uses both terms...).
In 33.4.2 (Fault Tolerance), figure 33-14 includes a node marked "PG" - presumably "protective ground". Is it appropriate to define PG within Clause 33, or to refer to it? I see that it is defined within Clause 14.3, but not apparently elsewhere within IEEE802.3. Where PG is used in the existing clause 14.3 it is first referred to in the text: "the ground for all common mode tests is circuit PG, the Protective Ground for the AUI".
Figures 33-15, 33-16, 33-17 and 33-18 show a ground or chassis symbol, but without the "PG" text, unlike Figure 33-14. Should the text "PG" be added? "PG" seems to be present in corresponding Clause 14 figures.
Figure 33-17 uses a different symbol for the ground or chassis node. Should this be the same symbol as for the other figures?
There are two instances of the ground symbols in both figures 33-17 and 33-18 - should any inference be taken about whether they are in fact connected together?
That's it - sorry to be a pedantic pain again.
Actually, the reason I've been looking at this is I'm trying to work out how to interconnect the RJ45 chassis ground, the "ground" on the primary side of the PD PSU and the ground on the secondary side of the PD PSU. It seems common practise to connect a high voltage cap from the transformer CT to the RJ45 chassis ground, but what happens when the PD is an a plastic box? Should the chassis ground connect by another capacitor to the secondary side GND, as I see in some PHY reference designs? Or by a low-resistance link? Or both?  If anyone who understands this can point me in the right direction I'd appreciate it (but not if you think I'm just looking for free consultancy!!! Actually, I'm happy to pay a bit to get this sorted...)
Regards -
Charles Palmer
Technical Director, DSP Design Ltd
email: charles@xxxxxxxxxxxxx
7 Tapton Park Innovation Centre, Brimington Rd, Chesterfield S41 0TZ, UK
ph: +44 (0) 1246 545 918