Learn English – Usages of “as” and “although” with approximately the same meaning

conjunctions

A. Huge boulders, far too big to be used as they were, were lying throughout the bed of the quarry.

and

B. Huge boulders, although they were far too big to be used, were
lying throughout the bed of the quarry.

Would anyone please show me if, especially semantically, there is any difference between the two bold parts?

Thanks in advance.

UPDATED: For clarification I had to edit my question. My Prof. has just shown me the following is correct and means the same thing. WOULD The sentences A and B, therefore, mean the same thing, as well? if so,why? why not?

1.Although it may seem straightforward, the argument is indefensible.

2.Straightforward as it may seem, the argument is indefensible.

Best Answer

"as", and "although" aren't interchangeable. Consider the following:

although they were far too big to be used as they were

You can combine both and it still means the same thing. The core statement is "they were far to big to be used", and I can add the word although to say that there's something wrong with them, and I can add the phrase as they were to say "in their current state".

Let's do an experiment and apply my logic to your update:

Although it may seem as straightforward as it may seem...

Okay the repetition sounds quite strange, but the meaning has been preserved. The core idea you're trying to get across is 'it may seem straightforward', and you can use either (or both) although and as to get the same effect. Although goes at the beginning of the clause and as goes at the end.