By giving his most common substitutes in the three berths -Steven Kitshoff (loosehead prop), Bongi Mbonambi(hooker) and Trevor Nyakane (tighthead/utility) – pretty restricted game-time throughout the Rugby Championship and also before it, the risk only swells that they will be under-cooked to varying degrees if suddenly summoned to the heat of combat early in a Test.
But guess how many, of all those caps, are starts? The answer is a flimsy two.
Both of those belong to the versatile Nyakane (now 32 total appearances), though neither has yet come under Coetzee’s charge … they were when Heyneke Meyer was head coach, and in respective victories over Italy (Padova, 2014) and Argentina (Buenos Aires, 2015).
Since then, Nyakane has gone on as a sub nine times while the incumbent has been calling the player-swap shots.
But at least the burly Bulls man knows what it is like to begin a Test match: Kitshoff, next to him on the “splinters” so often, currently sports 17 caps and, despite often enough making a rousing impact at some point in the second half of games, very patiently awaits that first summoning to the actual No 1 shirt for the Boks.
Admittedly in recent times, the veteran Tendai Mtawarira has lifted his game sufficiently to make it difficult for Coetzee to sit him out for a change as the loose-head starter and present considerably younger, 25-year-old Kitshoff with a crack at the outset.
But by sticking so rigidly to the status quo where Kitshoff gets around half an hour of activity, sometimes at best, it makes it challenging for the player to have to muster the required stamina in a hurry if injury woe, for example, were to strike “Beast” soon after a Test kick-off.
Even more at risk when it comes to possession of 80-minute lungs and legs in an emergency, if you like, is someone like the deputy hooker to Malcolm Marx, Mbonambi.
For the Stormers/WP player (11 caps, all off the bench) even the last full quarter of a game is something of a luxury, so he would really have to dig deep if pressed into action unusually early in an international right now.
It is possible that Nyakane, based on a poor 25 minutes during the collectively grim 0-57 fiasco against the All Blacks in Albany, will not even make the bench against Australia in Bloemfontein on Saturday; there is a strong case for extremely specialist No 3 Wilco Louw, fresh out of impressive Currie Cup duty for WP, to win a first cap (perhaps most likely as a sub, with Ruan Dreyer still the starting anchor).
But if he does dodge a match-day squad culling, Nyakane remains an especially vulnerable character if asked to play the lion’s share of a Test, because even at Super Rugby level he is often a reserve, or worryingly seldom given the luxury of playing a full game even when handed a No 1 or 3 jersey rather than 17 or 18.
His conditioning looks much better than it was several months ago, which is some comfort, but it is still asking a lot for him to go hammer and tongs for, say, 75 minutes at short notice; that is simply such a rare phenomenon in his case, even when operating a notch or two down from Test rugby.
At some stage – even with his tenure under renewed scrutiny and the engine room among his lesser hassles, perhaps – Coetzee would be well advised to give his broad front-row resources a more even spread of the hard yakka, don’t you think?