I've always heard it pronounced incorrectly as "ek setra". And now I'm wondering if it's unusual to pronounce the last word with all three syllables, as I do...

If you hate this as much as I do, don't listen to Sweet and Tender Hooligan by The Smiths. It's a great song, but the last minute or so is horror.

Yeah, true. To the point where I suppose it's basically standard in a bunch of regional dialects.