I teach secondary Performing Arts and have been teaching BTEC at level 2 and level 3 for the past few years. I firmly believe that for a subject such as Performing Arts, BTEC is a more appropriate qualification - it is practical, and puts a vocational context in place. The kids I teach in Yr 10 and 11 do a massive amount of work - much more so than when I taught GCSE. The work is more challenging too, in that it involves performing for real audiences (they've done other year groups at school, primary school children, invited audiences and ticketed events - it's taken very seriously) but because there is no written exam, the course is seen as a soft option.
However, I find the whole idea of "equivilances" a bit ridiculous - as the OP says, it's comparing apples to oranges.
I saw the article about this on the BBC breakfast news this morning, and agreed with the lady they were interviewing (can't remember her name) who said that the idea of asking a 14 year old to specialise (eg horse studies or whatever) is stupid - and I also agree that ditching a vast number of the level 2 vocational qualifications for schools is a good idea. There are still 175 courses to choose from.
Next year, my school will be offering all Yr 10 students one BTEC, so I'll be teaching BTEC and GCSE Performing Arts. Both the new spec BTEC and the GCSE Performing Arts spec involve considerably less work than the current BTEC spec for the students. I will be offering double award GCSE as it involves about the same level of expectation of the students as the single BTEC does. Both still expect less than the BTEC I currently teach.