Remember , JW activity is largely not designed to be productive - it is just really a "make work" scheme to qualify as "theocratic activity". This applies to all facets of "service" to the Society , be it all aspects of the ministry , building projects for future flipping , meetings etc. In one of Franz's books , the GB allude to this in one meeting when discussing the ministry and one of the GB members bewailing "What will the brothers do , then?" when discussing the lack of biblical basis for the preaching work.
I remember our congregation had an "assignment" every six months to do garden maintenance at an Assembly Hall. We would hire two minibuses and 20 - 30 of us or so would travel 2 and a half hours to get there , spend a couple of hours weeding etc which included at least 30 minutes ( probably more ) eating our packed lunches in the garden and then we would travel back home.
I was the "responsible" elder who organised things for a few years. I made sure that we always pulled into a McDonalds or KFC off the motorway on the way home and everybody enjoyed the day. For some of the older ones and single sisters etc who were lonely and weren't in the usual congregation cliques it was a real social highlight of the year and for the younger ones it was a chance to have a bit of a laugh with their mates and score a few easy spiritual bragging points.
Frankly what we actually usually "accomplished" in terms of work on the garden could easily have been done by a couple of local ( to the Assembly Hall ) volunteer JWs in a day , or a single professional landscape gardener. On a couple of occasions it was raining hard and all we did was basically sit in the Assembly Hall and had our lunches. From an efficiency angle the whole arrangement was a total waste of time in terms of what was achieved and spent in terms of coach hire , gas , time spent etc. But the whole point was that we thought we had done the "Lords Work". The letter writing is exactly the same as this. 100%.