I have 2 boys one just left LRGS last year after 7years and the other just started sixth form.
The pass mark isn't published and I think it must vary by cohort. I was also told to aim for at least 70% or more.
It also depends if you are 'in area' or 'out of area. If you are in area and achieve a pass then you are in. Remaining places go to out of area applicants in order of score. Any pupils who are out of area and achieve a pass but missed out on a place as their score wasn't high enough go on a waiting list which I assume is in order of score. I have quite a few out of area boys be offered a place from the waiting list after the initial round of acceptances are dealt with.
I suspect the pass mark is set each year to balance the proportion of in area and out of area places but have no evidence for this.
My boys have commented that some in area boys who scraped a pass can struggle to keep up as academic standards are high and ongoing testing is frequent.
If you work with them though I have found the staff to be very helpful and encouraging. There is a big emphasis on older students helping out the younger ones with yr11 students allocated to each yr7 form as a form 'prefect' and sixth form students providing mentoring to younger pupils who need a bit of support.
I have found the pastoral care to be good although we haven't had any major issues.
The really outstanding feature is the choice of extracurricular activities and societies which include both sporty and other choices which to me shows commitment from the staff.
My perception is that there is a relatively low staff turnover compared to some local schools. A number of staff are ex pupils.