Why does SMN have Physick?

[dinnertime]

or perhaps be replaced with Adloquium to make up for the poor healing potency (though I quite like Titan's shield, so this would not be my preferred option).

That would make no sense because Adloquium is a Scholar-exclusive ability. Also the last thing we need is people complaining that Summoner is getting too many defensive tools which will persuade the devs nerf, or worse rework the job again.