Based on 3 days there last week; useful but not essential.
We benefitted on a couple of multi pitch routes for both maximising the pitches and abseiling after. Some of the descriptions in terms of number of pitches are well off too.
on some longer pitch routes ( original ascents by army on 70-80m? ropes) you might well avoid having to belay at a very inopportune spots with the 60s. being 5m from a perfect stance and asking partner to simul climb a wee bit was what I remember