I believe we had this debate actually when that series was going on & i shall say again as i told you way back then.
McDonald keeping it tight is his strenght, thats clear. But its not a McGrath/Ambrose wicket-taking tight. He will bowl 6 balls on the same spot & good batsmen in tests should be good enough to respect that. But if they want to go into second gear againts him, they can do that & hit him off his lenght quite without much fuss, since he doesn't bowl any special wicket-taking deliveries.
In every match in SA as i've gone through before. McDonald basically fed off & was allowed to be economical because of superb the pace trio where in the 1st two tests. SA where never in a dominant enough batting position until the Capetown to take advantage of him "the obvious weak-link" in the bowling attack. He never posed a wicket-taking threat, AUS where better off picking another fast-bowler in SA, such as Nannes ATT after Bollinger went home injured.
While in Sydney although he gave the selectors the a 5-man attack of variety, that they have been seeking in that series after Wason was out injured. It severly weakened the batting. (Given in that home series, the selectors made the stupid error of picking Krejza & Haurtiz as part of 4-man attacks in Perth & MCG).
Thankfully though @ SCG & that entire home series, the batting outside Hayden & Hussey (to a degree) was never under Ashes 2005 pressure batting pressure (exposed technically) againts the SA bowlers. So a combination of continous solid batting & a balanced attacked enabled a win in Sydney, thus McDonald useless position in Sydney was again masked. Picking McDonald to give the side 5-bowlers, aided the balance of the bowling attack, but inversely affected the balance of the batting since McDonald is not a test match #6.
Firstly, no-one is talking about batting McDonald at 6 - if the wicket is greenish at Brisbane, then he is a viable option as a straight replacement for Hauritz
Secondly, there was no "superb pace trio" in any match McDonald played.
There were 2 extremely promising quicks in Johnson and Siddle, one relative dud (both Bollinger and Hilf were roundly criticised for their performances in the games in question and no short-sighted revisionism will change this fact) and no reliable spin option
In short, McDonald was easily the 3rd best bowler in every test he played
Thirdly, McDonald has been playing long enough in by far the strongest fc comp in the world for us to deduce that his record is no fluke
Fourthly, McDonald is unfashionable because he is an unfashionable cricketer - he bowls medium pace, is a gutsy batsman and no better than a trier in the field
However, whatever he does, he does well and consistently which is a vast improvement over many of the incumbents IMO
Fifthly,if he is so easy to hit, why dont people do it more often?
How about the fact that he is faaaaaaaaaaaaaar better than you credit him for being