2 questions concerning swords and disgraced standards

[Tarbicus]

1.
During the earlier civil wars, as well as Severus time and later until Galerius and Constantin the victorious emperors avoid celebrating victories over Roman troops (even if Severus wasn't even fighting a battle against them), especially in Rome itself. Dio reports how Severus entered the town but doesn't mention the standards. I guess it would have been seen as a pretty bad sign or even omen to carry sacred Roman standards in such a way, celebrating a "victory" over them.

Regarding the character of Severus himself, he was both ruthless and an innovator, not unwilling to go against tradition and shocking decisions. I wouldn't dismiss the notion of disgracing the standards too readily.

2.Severus dismissed the Praetorians but filled them with his own troops. Therefore he would have used the same standards again imho, so even if the members were disgraced the standards shouldn't have been.

I can't imagine the new legionaries wanting the old standards to be anywhere near them, given their history, and certainly not holding the spirit of their legion. Very bad juju, IMHO.

3. there are comparisons in Aurelius Victor, Eutropius and the HA between Severus and Constantinus whether taken from the same (lost) source or copied from one another (varries)....
....The HA messed up sources and incidents here once again, probably on purpose.

Possibly on purpose. Maybe the HA does the opposite of what you suggest and corrects the record?