Yea you're right particularly as Warne is so accurate he keeps the pressure mounting and MacGill very often bowls atleast one loose delivery an over, meaning the batsman will pounce at the opportunity and often be drawn into an unneccessary shot.
Similar with Lee and we will see what he's really made of when McGrath goes and he has to balance between two roles and hence really grind for his wickets. And if Tait continues in the frame then he may well be forced into adopting a new mindset because if there's two 'tearaway' quicks with erratic nature, the consistent grouping of pressure will no longer be there.
Also with kodos's statement about Pollock, he has 'recently' been in good form. Before that he's found it very hard to recapture his form and take clusters of wickets, usually resorting to bowling in tight areas to force an error or using his experience in persisting on the batsman; like McGrath at the moment.