Duplicate Action cards for Multiple players?

By midknightwraith, in Twilight Imperium

So it came up in a recent game I had, where two players in a space battle both had "Shields Holding" and a debate ensued about whether or not the second player (in Initiative Order) could play that card after the first player had already played a copy of that card. From 2.6 bullet 2 - Multiple action cars with the same name cannot be played during a single timing window to affect the same units or game mechanic.

The issue seems to be the use of "or game mechanic", it is clear that two different players playing "Shields Holding" are affecting two distinctly different sets of ships, but "game mechanic" could be used to refer to a Space Battle Round or even just combat Round Hits which clearly both cards do impact.

It was also argued that because this card uses "your" it technically is two different timing triggers. The issue was resolved and we moved on, but with a promise of further research. Which bring us to now.

It should also be noted that the following cards also have similar issues, so I am asking about those as well.
Maneuvering Jets
Morale Boost
Skilled Retreat

Morale Boost and Skilled Retreat in particular have more generic timing windows, not using the "your" in the trigger; while Maneuvering Jets does.

My personal feeling is that everything except Skilled Retreat could be used by opposing players. Morale Boost uses "your" in the effect, but I could definitely see the logic in the argument that it could not be played by both players as they are reacting to the same trigger even though it is affecting different units.

Skilled Retreat seems like as soon as one player played it, the other player could no longer play it because once it resolves the combat ends in a draw.

So what is the answer for these cards when two opposed players both have copies of them, can the second player also play them if the first player does, or not?

Edited by midknightwraith

I would want to read exact wording to be sure, but it sound to me like they are different timing windows and each player could play one.