[Grammar] simple past vs. present perfect + "intention"

[matt234]

This is probably bothering me more than it should. I am wondering whether to use "It didn't even seem to be his intention", or "It didn't even seem to have been his intention". I am talking about a fictional character and a relatively specific point in time (but open-ended).
Perfect would normally be the safer option, however I didn't use perfect in other contexts of the text (with less ambiguity, but where an alternative was possible), and coherence can also make a jarring impression when broken. It would change the position of looking back in this case.

Edit: I'm adding a different option but which is actually present perfect: "It doesn't even seem to have been his intention." I somehow can't identify the perfect I used above right now. Past perfect, maybe. The "seem to"-form is making it more complicated.
In any case, I think the more rare "didn't seem to be his intention" is actually fitting in this case, because of its open-endedness or prospective nature, which is projected to a point in the past. "[D]oesn't seem to have been" seems to be without problem (looking back), whereas "didn't seem to have been" doesn't make much sense to me right now. In any case this is a mess. I lost a more explanative post I made, and since then I can't explain it any more. Maybe someone can exclude an option or two.

 

[Raymott]

You need an action that occurred after deciding that "it didn't seem to be his intention" to use "seem to have been". (I'm leaving 'even' out).
1. A man goes to trial and can be found guilty of murder (if it was intentional) or manslaughter (if it was not intentional). A witness says, "It didn't seem to be intentional" (at the time it was happening).
2. The jury decides that, on the evidence, "it didn't seem to have been intentional".
In 2. there is another step away from the action.
It's a similar concept to using the past perfect rather than the simple past - and that means that not everyone would agree on a specific case.