Could be cultural differences but healing other alliance members is not expected in my group; it's a bonus if you do it. I play on pad too and find it hard, but with our AoE healing removed I find healing my own party a full time job most of the time. When I have time or the opportunity I'll sling heals at people in other groups to avoid losing anyone, but not if I have to flick my targets all over the place at the expense of my own party.

If they want to zigzag around like maniacs and refuse to come back when they're being focused despite being a group of 8x SAM with nobody switching to healer, they're just going to die. Targeting alliance members on a pad is absolutely horrible in this game (which is weird because it was ok in FFXI).