Two days after his pack were taken apart by Ireland, Humphreys would make no attempt to hide his anger and frustration. "Dreadful", "awful", "a shambles" were all phrases he used to describe their play, and his frustration was made even stronger by his conviction that the players have enough ability but need to find the mental strength, concentration, belief and confidence to deliver.
"You can ask me all the questions you want but the fact is that we were awful and we're not hiding away from that," said Humphreys yesterday. "It's nowhere near the standards that we set ourselves, nowhere near where we want to be and nowhere near where we want to go.
"You can talk about what it's going to be like against England [at Murrayfield on Saturday], but that's not the point. We don't need to have high spikes and low troughs the whole time, the standards we set must be constant and the internal motivation must be the driving factor in our performance, not the team we are playing against.
"There is no hiding away from the fact that we were dreadful in every aspect of forward play at the weekend; every aspect.
"You can talk about honesty, but this is fact. We were awful. And if you say that we'll turn it around because we're playing the Auld Enemy and we'll put on a performance, then it still doesn't hide the fact that we were awful [against Ireland]."
Such fierce criticism suggests that there is bound to be changes when the team is announced tomorrow, a day later than is normal. Though Humphreys' frustration at the lack of options in the front row was clear, he does feel that there is genuine depth in the second and back rows, and it could be significant that the only player singled out by name was Jonny Gray. The teenager captained the A team last week and Humphreys has held him up as the flag bearer for the next generation.
"It's not about me, I don't feel let down, it's not a personal thing," said the coach. "It's about us as a group going forward. Where do you sit and what do you represent? If somebody was to ask me right now what does our forward pack represent? Well, I'm struggling."
Every aspect of the forward performance will come under scrutiny on Saturday. Humphreys derided the set piece as "a shambles" since Ireland had been placed under pressure three times, only for the Scots to make a mess of the attacking lineout. "It was nothing that Ireland did, nothing," Humphreys added. "They were nowhere near winning the ball off us. It was our error.
"The key things that we're talking about applies right there, at that moment. We win three, or even two of those lineouts and all of a sudden we create more pressure on them. We're there, keeping the scoreboard ticking over. You could say we were dreadful in that first half, but we created many opportunities. What we didn't do was squeeze them with the opportunities that we had at set piece. That's what cost us the game."
Another chaotic lineout gifted Ireland possession on Scotland's line just before half-time and led indirectly to the try which turned the game. The scrums were a mess, the maul a disaster and, although the breakdown statistics were more even, Ireland won all the battles when it mattered.
Of those who will potentially be dropped, neither Tim Swinson nor fellow lock Jim Hamilton can feel their places are secure, and the back row is certain to be rejigged to add a bit of variety and perhaps even a specialist openside flanker. However, there has been no talk of players being added to the training squad.
"We're still a long way short of having the depth that other teams have," said Humphreys. "We have to look longer term as well as the short term. What is our development process? What do our age grade teams represent? What are the principles that they are based on in terms of their forward play?
"England, at the weekend, will expect to beat us. But the game changes when it's you who are squeezing the opposition. If you release that pressure through your own errors, you allow the opposition into the game, allow them to create.
"That was what we did [against Ireland] and it wasn't about anything other than simply sticking to what we needed to do.
"It's not easy to play for Scotland. These boys have to battle against the perception of what they are - everybody who comes here will come at them because of the perception that they are competitiors, but just that. Just that. That perception can only change through the deeds we produce."
"I think these guys can take us to where we need to be. It's just about the mindset of 'can you believe you can take us to where we need to be?' Winning breeds confidence. Going out there winning things, winning big things, breeds confidence."
Humphreys has two training sessions today to try to turn things around, although the performance of Scotland's forwards against the Irish is still likely to hurt for some time.