Pog was bad and he was not bad:
The good: it's his best result in a World's TT, almost on the podium.
The bad: the terrain suited him and a good Pog should be able to become 1st of 2nd in this field.
We had Remco with zero chance of having jet lag, perfect prep, fresh vs. Pog who came from Canada where he raced hard, to Europe to Rwanda (so 100% chance of having some jet lag), not having had too much down time this year. Either Pog is tired and won't shine in the road race, or he's jet-lagged (a bit like Remco after his vuelta win, underperforming in the TT in Wollongong), and with enough rest and acclimatisation, he'll feature as always in the RR.
With regards to Pog's TT in the TdF: those at the end are mostly won by the freshest man, not always by the (intrinsic) best TT.