There is no subjunctive mood in English.

<"If I were there at that time", which is practically timeless in and of itself.>

So, "we were there at eight" is also timeless, right?

I didn't know that "were" was timeless.

Baugh AC (1935). A history of the English language (New York: D. Appleton-Century Company).

Section 235, page 409:

There has been some schoolmastering of the language. The substitution of you were for you was in the singular occurs about 1820, and it is I is now often considered a social test where propriety is expected. What was left of the subjunctive mood in occasional use has disappeared except in conditions contrary to fact (if I were you).
........

That's says there is no subjunctive mode, but only one or two subjunctive constructions.

>>So, "we were there at eight" is also timeless, right?

I didn't know that "were" was timeless.<<

That, of course, has an associated time expression as well there. I meant just that "were" seems to be less associated with any particular time (think "If you were here", which is effectively referring to something in the present versus your example), in and of itself, than using "was" in its place, at least in the dialect here.

>>You are a bit of a bore at times, Clive. I've written numerous papers with both synronic and diachronic viewpoints.<<

I wonder where you got the name "Clive", which you have been calling me for whatever reason as of late, from.

Another note is that, just for the record, how many papers you have written does not really matter here.

<I wonder where you got the name "Clive", which you have been calling me for whatever reason as of late, from. >

You remind me of a Clive on another forum. Are you he?

>>You remind me of a Clive on another forum. Are you he?<<

I myself have never gone by the name "Clive" (or for that matter known anyone who has gone by that name), so then you must be confusing me with another person here.

<I myself have never gone by the name "Clive" >

Why do you write "I myself" there? Isn't "I" enough?

Many native speakers say things like "David and me saw a good film last night". Would anyone say that that is correct use in any dialect?

>>Why do you write "I myself" there? Isn't "I" enough?<<

Actually, I cannot explain the specifics of such usage of reflexive pronouns myself, such as when they are used, or when different positions they are found in are used; while certain cases can be easily chalked up to meaning "in the case of <subject>", not all cases in my usage can necessarily easily be explained as such. Hell, this is likely something that one could easily write an entire paper on in and of itself if one really wanted to. Anyways, this is likely influence from my spoken usage in some register or another, even if I really cannot state the underlying "why"s here.

<<Many native speakers say things like "David and me saw a good film last night". Would anyone say that that is correct use in any dialect?>>

Are you just going to go down the list of hot-button issues for prescriptivists/descriptivists? There's no need for that.

>>Many native speakers say things like "David and me saw a good film last night". Would anyone say that that is correct use in any dialect?<<

Yes. The idea that one would use "I" rather than "me" here is a purely prescriptive notion with no real basis in actual English dialects. In fact, when this prescriptive notion is not intentionally applied, the default usage in many if not most English dialects today in cases like this seems to be to actually use oblique case rather than nominative case pronouns, with nominative case being limited to clauses where the pronoun in question is the sole subject. Of course, the specifics of such are likely more complex in reality than what I stated above.

However, there is something that seems rather weird about your sentence, which is while your sentence is grammatical, the word ordering subjectively seems rather off. It seems that the most natural ordering here would actually be "me and David" rather than "David and me", counter to the order prescribed by those who state that it should be "David and I". This, though, is less strongly favored than cases like "me and my friends" versus ?"my friends and me", where, while the latter is technically grammatical, it is very strongly disfavored in practice. Again, this is likely far more complex than what I have stated here; this is the kind of subject you could write a published paper on if you wanted.

<Are you just going to go down the list of hot-button issues for prescriptivists/descriptivists? There's no need for that. >

The question was a simple one and in response to two NES here saying that NES never make mistakes. That example is a common mistake, isn't it? So, is it really a prescriptive vs descriptive thing, or is it an error that should be eradicated from all dialects, as it has no sense in usage.

<Yes. The idea that one would use "I" rather than "me" here is a purely prescriptive notion with no real basis in actual English dialects. >

So it's correct to say "Me saw a good film last night"?

<However, there is something that seems rather weird about your sentence, which is while your sentence is grammatical, the word ordering subjectively seems rather off.>

What does "rather off" mean there?

>>The question was a simple one and in response to two NES here saying that NES never make mistakes. That example is a common mistake, isn't it? So, is it really a prescriptive vs descriptive thing, or is it an error that should be eradicated from all dialects, as it has no sense in usage.<<

One thing here is that this is most definitely a matter of prescriptivism versus descriptivism. To say that a native usage which is not simply a matter of misspeaking, which this is most definitely not, is an "error" is prescriptivism in and of itself.