The Blues scored a mammoth 16 tries to beat the Italians 104-12 at BT Sport Cardiff Arms Park - their highest ever European points tally.
There were 12 different try scorers, with winger Richard Smith the only player to reach a hat-trick, while Gareth Anscombe and Gareth Davies split the kicking duties.
The Blues finish the pool with a trip to Grenoble next weekend and, knowing that a win will send them into the quarter-finals, John admits that the preparations have gone well.
"We have to go there and do the job against difficult opposition," he said.
"If we play like we have against Rovigo and look after the ball then we will have a good chance of scoring some tries. However, we have to apply ourselves in a potentially more difficult game away in France.
"We have put ourselves in a good position after getting what we needed against Rovigo. It's going to be a big week for us.
"The priority was to get the win and get the bonus point. You can see from their actions that this meant a lot to them and their attitude remained focused throughout the game which was very pleasing.
"We were pleased by the boys' overall commitment. This was typified by Cory Allen racing back 60 metres or so to stop them scoring that one try when they had intercepted.
"It's not necessarily about the amount we scored but the way and how the boys applied themselves.
"Scott Andrews has to have a mention for playing in the second row because we prepared well for that and he is an excellent rugby player.
"You could see that out there with the touches he gave during the game. He should be praised for the attitude he has shown this week."
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