Despite running in six tries in a 41-10 rugby World Cup win over Georgia on Sunday to make it two wins out of two in Pool B, England were far from impressive.
Coach Martin Johnson was fuming afterwards and went as far as to say they would be departing the tournament early if they did not rapidly improve.
That message was not lost on the players, who held nothing back in their post-match analysis meeting.
"It's the same after any game, you review it. Some are nice and easy, some are harder and some are a bit more brutal," Thompson told reporters. "This was a hard meeting just because we've got such high standards."
England had benefited from being able to talk honestly to each other and taking criticism on the chin rather than harbouring grudges.
"That's what this group of players is all about: 'honesty is the best policy' or 'stab you in the belly rather than in the back', that's what we need," he added.
"We've been together a long time and the last thing you want is for things to get comfortable. Sometimes everyone needs to give each other a little pat on the back or a little boot up the backside and that's what's happening.
"It's perfect for us, it's like a relationship, sometimes you get a little bit stale, don't you? Sometimes you've got to have a little bit of an argument and have the old make-up afterwards."
Thompson, who made his debut nine years ago, was part of the 2003 World Cup-winning team and has seen it all before.
"In 2003, we had exactly the same thing after the Samoa game when we came close to losing. We had to move on then and now we've got to make sure we do keep improving," he said.
The team knew they had not been firing on all cylinders against Argentina and Georgia but the fact that England had won two from two despite not playing their best rugby was an encouraging sign, Thompson said.
"Sometimes if you are winning ugly and being harsh on yourself, sometimes it's a good place to be because you can get better," he added. "But we're two from two and we're moving forwards and today there was a great buzz in training."
England's next game, against Romania on Saturday, should be their most straightforward but Thompson said the forwards in particular were bracing themselves for a stiff test and highlighted the qualities of their captain Marius Tincu.
"If you look at what they've done to teams ... it's not one big scrum. They are a very good scrummaging outfit. I thought the Georgians were good and they're big but I'd say the Romanians are a tougher scrum," he added.
"I know what Tincu brings to the party and whoever's playing against him is going to have a tough day and it's going to be a good competition."