The general rule is that the demands of the professional season are too much for most and there will be periods in the year when performance will drop off for some players.
An enforced injury break is therefore not the disaster it is portrayed as being. Take Smith as an example: he's got a solid base of game time under his belt despite missing a couple of weeks due to a head knock earlier in the campaign.
His current ankle strain has prevented him from travelling to South Africa which is no bad thing. Last year a handful of the Highlanders' test players had to travel to the Republic twice for Super Rugby and then return for a third visit with the All Blacks. They also had to travel twice to Argentina.
The Crusaders' All Blacks were also subjected to three trips to South Africa and it was no wonder that Hansen reckons his side crawled over the line in November with laboured victories against Ireland and France.
Smith should reach the Lions series fresh and firing. The same is true of Israel Dagg who should return in a couple of weeks and the fact he too has missed the Crusaders trip to Africa will pay dividend later in the year.
Both Read and Jerome Kaino will be short of rugby coming into the Lions series but if there are two athletes who Hansen would trust to play a test undercooked, it would be those two.
Time off now is time in the bank down the track and inevitably when some players begin to flag later in the year, the likes of Smith, Dagg, Read and Kaino should have plenty left in the tank.
The same is true of Nehe Milner-Skudder. He'll be gutted to miss the Lions series should that be his fate, but the consolation is that he will be, presumably, in excellent fettle later in the year.
And that's why Hansen will be relatively relaxed about the state of play. The ongoing battle Coles is fighting to overcome delayed concussion symptoms will be the only concern beyond the normal.
The fact Coles is suffering symptoms more than six weeks after he last played is further indication that concussion is the most dreaded injury in the game.
Medics can't make any knowledgeable or accurate predictions about when or even if players suffering from concussion will be cleared to play and while everyone is hopeful Coles will be back before the Lions arrive, there's no certainty that will be the case.