Subjunctive Nuts...
I'll confess I'm a slight pedant in English, even when it comes to the subjunctive. And, In English, to be a pedant about the subjunctive, you really do need to very pedantic... Because it's so rare anyway.
But I'll give you an example. Recently my wife & I were touring local schools where we might send our son, & on the outside wall of one of them I saw a sign, which reads something like, 'If this building was made of gold, it would weigh xxxx tonnes'. This caught my attention whereupon I vented my spleen at my wife, grumbling that it should say, 'If this building were made of gold...'. My (long-suffering) is well-used to me, so she knows how to handle this kind of tontería. She quipped, 'Well, that's that, then: we won't be sending him to this school. Why don't you write a letter of complaint to the head teacher ?'.
Ok, so there, I get it. The subjunctive matters.
Or does it ? Really... ? Maybe my wife's right after all (she's seldom wrong)...
I'm sitting here listening to an audio lesson on the subjunctive, & I'm understanding it all... Except, I really do wonder whether it's necessary... Even in Spanish...
(Calm down, please... It's not like I'm sitting on the Bible, or anything like that.)
Of course, not for a momentito am I suggesting that Spanish get rid of it (because that school's not really made of gold), but to be honest I cannot for the life of me see what difference it actually makes to comprehension. Aye, style, aye, it might sound a bit weird not to use it. But surely, for goodness, subjunctive or indicative, it'll mean the same...
Please, tell me how wrong I am... 
5 Answers
'If this building was made of gold, it would weigh xxxx tonnes'.
In Spanish the subjunctive is absolutely necessary in this sentence. If you were to use past tense fue, it would sound very strange although it would probably be understood by most people even though the nuance would be destroyed. And don´t forget that at one time in English the subjunctive was used much more that today. Past tense is accepted in its place because Oxford can´t make people speak correctly.
I agree with your wife even if she is only joking. If this sign was in fact written by the faculty, I wouldn´t send my kid there either.
You are very right. It should've been "were". Unfortunately, English has almost lost it and you can recognize the error only because you have studied etc. Whereas, in Spanish like Julian said, the past tense indicative does not make any sense.
That's the difference.
When you get right down to it the subjunctive is not used in Spanish because of grammar rules, it's used because people use it when they communicate. You and I cannot make it go away by not using it, and as "foreigners" we would sound stupid if we didn't use it correctly.
I live in the United States and while I resent the often unspoken implication that British use English better than we do, I will concede that there is a real "dumbing down" of the English language here. I hear things like "Me 'n her was jus' lookin' at them" for "She and I were just looking at those" all the time. Yet these troglodyte co-citizens of mine are always understood by more intelligent people so they are using a valid means of communication. I wouldn't wish such a catastrophic assault on any other language such as I witness on my own. Embrace the subjunctive. If it were obsolete, we would know.
I always enjoy your posts even when you write in that Scottish dialect that I can't understand.
Is the subjunctive necessary? Well tons of languages have no such thing (many don't even conjugate their verbs). So strictly, it's never necessary. In fact no grammar rule is.
Are genders needed like in Spanish? Nope, Chinese doesn't have them.
Are subject/object pronouns needed like in English? Nope, Jamaican Patois uses the same word for "me" and "I". In fact, many Native American languages don't have pronouns.
Is the copula (the word "to be") needed like in French? Nope. Arabic and AAVE get along totally fine without it.
Is a topic-marker necessary like in Singlish? Nope, English gets along fine without it.
Is a three-way distinction for proximity needed (esto vs eso vs aquello) like in Japanese? Nope, Hindi doesn't need it.
But notice how there are languages that have the above features baked into their grammar. Because nothing is strictly necessary, it's just something native speakers do.
It would be impossible to eliminate the Spanish subjunctive without introducing some Modals into the Spanish language and that would never do would it?
That it would make most of those 10 inch thick Spanish verb books obsolete would never do.
If it were up to me (the past tense shows that it is not) I would scrap the Spanish subjunctive and use my 10 inch verb books as door stops.
I guess I am just a spoil sport (how would Spanish speakers be able to identify a non-native Spanish speaker and have a little giggle) but where would the English language be without the word would?
