Beyond consistently selecting Fraser Forster, Oriol Romeu and Virgil van Dijk, the Frenchman has regularly overhauled his selections as he balances their involvement in the Premier League, Europa League and EFL Cup.
Wednesday evening's 2-0 victory at Arsenal took them into the semi-finals of the League Cup, where it would be expected that should they reach the final Puel would play his strongest XI.
The manager, however, had been asked about the fact his rotated captain Jose Fonte is yet to sign the contract he has been offered, and he told reporters: "I don't know my first team with 11 players. My first team has 22 or 23 different players and this is important for me.
"Jose has a contract and after I don't speak about the contract of the players.
"It's a story between the club and the player and this is private."
Fonte, who joined Southampton while they were in League One, had long spoken of his ambition of representing the club in European competition but he has been rested from each of their five Europa League fixtures so far, and the manager said: "For me all the players can play different competitions.
"There is not one player for this competition and another player for another. For me it is not this.
"It is to see and to respect the good physical level for every player and to find the good balance between players, to practise every time our identity.
"We can see (last Sunday's 1-0 win over) Everton; it was a fantastic game physically, the intensity of the players, and Jose also had a strong game.
"This is possible if every time they all have good energy, good physical levels and can play at their maximum."
As he did against Arsenal from the team that overcame Everton, Puel is again expected to make changes to his XI when Southampton on Saturday visit Crystal Palace in the Premier League.
He added: "It's important for the players to understand the philosophy and keep every time the good attitude.
"The most important (thing) is to stay with good concentration about our level and to prepare this difficult game against Crystal Palace. It is not the situation of every player."