At level 42, I have only just started practicing shard-farming in earnest,
and since I am new to it, but trying to learn and practice the techniques taught by veteran champion hunters (about speed and moving quickly from zone to zone), I have been working mainly on lower-level maps, just to get a feel for it.
I'l burn through maps on mudfalls, glaciella, narwhalimbus, yeti, and grotto.
However, even on Yeti and Grotto, I haven't been calling alies for assistance.
I had mass heal waaaay back when I was a wee monk, but decided to abandon it in my late 20s when I accidentally used a potion to re-spec (and have never re-spec'd since), and I personally don't see it as being that useful in this case.
First - I have plenty of allies to call if one dies.
Second - I haven't encountered champs which I couldn't solo, in my current route.
I should point out that my opinion is still that of a novice champion hunter, so it may be skewed by lack of experience.