No offense taken. I could have worded it better!
I. personally, would love him to take these subjects, as, I too, believe they provide him with options in the future, but, if he wanted to take an apprenticeship, or a vocational course, I would fully support him in that as well.
The workload does concern me though, with the step-change, and one thing that came up in discussion last night has come up in this thread as well, namely, does he really enjoy those subjects? I think this is a huge factor, and whilst he love Chemistry and Maths,
he is not a huge fan of Algebra which forms a large part of Mathematics going forward, and he also finds Physics boring which does concern me slightly.
His teacher indicated that he would find the Economics/Business quite easy, although it does contain quite a bit of work, so the scenario you've mentioned might very well become the case, and depending on what route he chooses, one of the Sciences could perhaps fall away after the first year.