Could someone please explain to me whether/why it's better to do foundation maths for a student who struggles and would be a borderline C/D in the higher level paper? I know you can't get higher than a C in foundation but I've also heard that the questions are much much easier across the whole paper so it's easier to get the C in foundation than it is in Higher.
I am having a discussion with someone who seems to think it will be easier to get the C in the higher level because the student only has to know a few topics well, and get those questions right (for about 25% I think, to get the C?) whereas in foundation they need to get 80% covering many more topics. But what if those topics the student knows well don't come up? 
But I've also been told that some of the questions in foundation level are things like 'measure this line with a ruler' 
So getting 80% shouldn't be beyond the remit of most people who do not have SEN.
My argument is that unless you are predicted borderline B/C at higher level you are better to play safe and take foundation, because your C is going to be much easier to obtain, and a C is what most people require to move forward with anything, whereas a D at higher level is useless for most courses at most half decent universities. (not that this person wants to study anything with a maths element.)
Thoughts please?