Mouse-wrangling aside, I really don't think what he's asking for is unreasonable. A lot of the time, you want to drop a ground-target under a bunch of mobs. It'd be nice if you there was a way to say, "drop it under this mob, don't make me waste time positioning it, just drop it here". This is especially true for players who don't use mice, such as the majority of Playstation players.

It would also allow ground-target aoes the flexibility to be used in macros. For example, it'd be nice if:

/action "Shadow Flare" <t>

would place your Shadow Flare on the ground centered on your current target, bypassing the need to position it with controller or mouse. We'd still want the option to position it normally - sometimes you want to place an aoe where there is currently no targets at all - but this additional functionality wouldn't be at all unwelcome.