Priest mouseover macros delay

[Tirkad]

Hi everyone,
I am levelling a priest healer, and while using the mouseover macros with the same general layout i use on Tirkad i noticed that on my priest they have an annoying delay in capturing the mouseover target. My macros are set as follows:

#showtooltip
/cast [@mouseover, noharm, exists]
/cast

The problem (that i never experienced on Tirkad) is that if i change the mouseover target too quickly, or if i try to chain cast on different targets, the interface bypasses the mouseover target and simply cast them on me. I have made some tests on a druid alt too, and the mouseover macros seem to work fine on him.
Can anyone help me?

[TeaLeaf]

Never experienced that myself - I'm using Grid/Pitbull and mostly direct mouseover macros, with a few additional Clique binds.  What are you using?

[Tirkad]

Since cata, i decided to rely only on the standard interface for the healing frame: it's customizable in shape and many features, such as buffs/debuffs shown, health remaining/from max, and so on. But the best feature is: i don't have to update it after each major patch.
Anyway, i solved it. Just delete the last line of the macro, however this will make the macro only work if you mouseover the target: it will not cast the spell on yourself if you point in any part of the screen without a friendly unit.