It was a new course in 2010 replacing BScience and Technology and Bachelor of Liberal Studies and is administered by the Science Faculty. Since those two courses previously had low cut offs, the university did not want a high cut off for the BLAS, the marketing team offer this course to students who did not get into their degree of preference, and recommend them transfer from there.
It was a course developed with 'employers' (dont really know which companies they collaborated with to decide on this) to improve the skills the skill that students need in the work place - this is covered in the BLAS's compulsory units of study, these units are also offered to students from other degree programs.
For a student with an ATAR well above the cut off, they may still take 'advanced' units of study so they won't necessarily be with the 'less capable students' in their course all the time.
Hope that helps.