I beg to differ, and will agree about 90% with Nrieh.
As an Op healer(mirror) I can survive a good long while and heal a good amount. I average about 350k healing in non-Huttball games, and typically 30-50k less than my lovely Sage friend, who spams her AOE heal.
I actually prefer not to heal and run, but that is because I tend to get focused by the Pubs on my server when I play. I like to bunker down in cover (No Force Leaps or Charges), or if not available just crouch, and spam my HoTs and my Diagnostic Scan to regain energy and bait interrupts. If you can bait an interrupt, then those HoTs you placed that supposedly only prolong someone's death will be worth their weight in gold when you cast your Kolto Injection (Underworld Medicine) on them for 5.5k (Full Champ, critted). If they don't take the bait, pop a Kolto Infusion (Other 1.5s cast heal) to bait the interrupt again, because you should always have a Tactical Advantage (Upper Hand) ready just in case, and for the extra healing power. This also gives you a chance to place down an Explosive Probe (Sabotage Charge) on an enemy, should you have the spare energy (which you should) and time (which you might).
I actually agree that our mobility is slightly hindered by Kolto Injection but with the right amount of alacrity it can easily be fixed to a point that gives us decent mobility, but doesn't make us totally mobile, and OP.