The naming of an unchanged bench was portrayed as a vote of confidence by Scotland's head coach yesterday even though two changes had been made to the starting XV for this week's meeting with France.

The decision to drop flanker Rob Harley from the back-row was never likely to mean a place for Ryan Wilson, his Glasgow clubmate who made his Test debut off the bench last weekend and is a specialist No.8.

Leaving Al Kellock, the pair's captain at Glasgow, among the replacements and promoting Grant Gilchrist to join Jim Hamilton in the second row was rather more of a surprise.

"This is one of these funny ones," said the caretaker head coach Scott Johnson. "We are really, really happy with what Al [Kellock] brings us late in the game – that is a bit of maturity and a bit of composure and we really enjoy that. I spoke to him before the campaign because I have got a lot of time for him as a person and as a rugby player. I want to be true to the fact that Al has signed a two-year extension on the back end of it but it is doubtful that he will make the final campaign in the World Cup.

"We want to suck his brains while he is here and it is really important that the younger fellows learn because he has forgotten more than most know in certain areas of the game. We wanted to be true to that. We sat down and said 'okay, how's our scrum?' We have got a pretty good scrum, a combative scrum and Gilco [Gilchrist] likes that. Rather than move a lot of people, it was an opportune time to do it."

There will be no doubt that Gilchrist likes the rationale and Johnson can be pretty confident that Kellock is too much the senior pro to rock boats, but whether combativeness alone is enough may depend on the management's belief that France will present a more straightforward physical challenge than the wily Welsh did last weekend.

Setting aside Kellock's ability to make an impression off the bench – reminiscent of Matt Williams's fondness for playing Jason White and Nathan Hines as "impact players" – the memory of Gilchrist's only previous Test involvement may have been a factor.

Johnson was, after all, still settling into his job as Scotland attack coach when Kellock was preferred to Hamilton against Tonga in a defeat which proved to be the denouement of Andy Robinson's reign as head coach.

"That was my first experience and it was not a great one," said Gilchrist, who was preferred to Hamilton on the bench that day but was not brought on. "There was no hiding about from the fact it was a poor result and everybody was in a dark place afterwards."

Just how far Scotland have come will be reviewed after Saturday's meeting with the French since they have achieved something of a breakthrough with successive Six Nations wins for the first time in a dozen years, but did so thanks to a defeat of their usual Wooden Spoon rivals Italy and a backs-to-the-wall effort against Ireland.

Saturday's match will decide whether the team finishes in the top half of the Six Nations table for just the third time in 14 stagings of the tournament.

The other change is less surprising as Al Strokosch returns to the side in favour of Harley, who performed well on his first two starts against Italy and Ireland but, along with captain Kelly Brown took something of a beating at the hands of Sam Warburton and the Welsh pack last weekend.

"I think there was a bit of a balancing act there," said Johnson. "We know there are some issues in our game and we are trying to work out the differences. I am not speaking out of school with Rob because we love the energy he provides, but he has got to be a little bit more efficient at certain things he does and we think that Strokosch can provide that.

"It is a balancing act, because sometimes if you don't get into the 15 then you are not in the 23. His [Harley's] skill set suits us to start but do not necessarily mean [he makes] the bench. Strokosch provides us with something, it goes hand in hand with Gilchrist's selection. Rob has some elements of his game he needs to improve on and he has acknowledged that. We need to go back to the drawing board but [he has had] three tests on the bounce and that will be good for him."

He admitted it was something of a risk to go without either a specialist openside in the team, exposed so badly last weekend, or on the bench, particularly when the "Killer Bs" back-row could have been reunited.

However he feels John Barclay's form is not yet good enough to justify his inclusion, which is why the option of having Wilson available as an extra ball-carrying option has been retained.

"[Barclay] did come into consideration," Johnson said. "The reality is that Kelly has done pretty well for that position and without being unfair on the people we are talking about, their form has not been through the roof either. We have got to be fair here that we are comparing apples with apples and not deluding ourselves.

"In this case John has come back but is not the back to the form that we want him to be, not just yet. It was down to the wire but the fact is Kelly has done some good things."