I often think you are better with a sheep farmer at a difficult lambing as they have assisted many births compared to most vets. And round here some of the farmers have hands like shovels. I know many people say women are better at these things because of smaller hands but lets face it if a big lamb will come out a big hand will go in.
At the end of the day it is experience that counts not size...is it not!

I quite agree. Many years ago we used a very experienced vet who had the biggest hands you've ever seen and my heart used to sink if he came out for a difficult lambing.
Having said that, if the lamb inside was still alive, he never failed to get it out safely.
On reflection though - Julie maybe your elderly tenant needs to rethink his pregnant ewe strategy. It is unusual for an experienced shepherd to end up with that situation 2 years running. At this time of year I presume he's lambing inside so giving his ewes concentrates. So maybe he needs to feed them all as if they are expecting singles, so avoiding the problem of the oversized (and dead) single lamb.
Possibly he might be better delaying lambing for another month and lambing outside, whereby the ewes, getting more exercise tend to be fitter and have less problems.
Gone are the days when I expect a load of problems and sleepless nights at lambing time. I now lamb in the middle of April. The sheep stay outside apart from the very rare instances when I might pen the ewe and lambs up for a couple of days. While pregnant they are fed on good hay and feed blocks only, and as soon as I know the ewe and lamb are bonded they are moved onto fresh grass which is at its most nutritious at this time of year. There are no concentrates that can match the boost in milk production and growth rate of animals on fresh spring grass 24/7.
I rarely get lambing problems now as my ewes are fit, not overfed.