The Sharks won just seven of 22 league games last season in a forgettable campaign that saw them finish 10th ahead of only Worcester and relegated London Welsh, yet Diamond is moving on after watching his side cling on for an impressive opening-day win at Kingsholm Stadium.
"Last year is another season. The year before, we got to the Heineken Cup and nobody talks about that, do they? There is no point bringing that one up," said Diamond.
"We are at Kingsholm today, for goodness sake, and Gloucester came out with a real passionate second-half and took the game to us. We held on in the second half but that is the character we showed in the latter half of last year where we won seven or eight of the games we played.
"We have now come down here and, if you get a bonus point, you are happy, so to win is a great result for the club."
The Sharks were 19-3 up in the 52nd minute after centre Andy Forsyth scored their second try of the match, the first coming from wing Mark Cueto, with fly-half Nick MacLeod and full-back Tom Arscott sharing three penalties up to that point as woeful Gloucester could only record a penalty from Freddie Burns for their efforts.
It seemed an odds-on Sale victory but Gloucester, who were booed by their own fans at half-time, finally clicked and managed to claw themselves back into the game.
Centre Henry Trinder stormed through a gap for a try that Burns converted and two further Burns penalties took Gloucester to within three points.
Gloucester threw the kitchen sink at Sale to win game in the last 10 minutes but they could not break through and a late drop-goal from replacement Joe Ford killed off the home club's hopes to give Sale a happy journey home.
Diamond said: "We managed to show a bit of character in the final quarter and held on. We were defending for a lot of the game but Nick MacLeod and Joe Ford gave us field position and we managed to contain them."
This was the first match at Kingsholm where a non-TV game has had a television match official - every Premiership match will have one this season - and, for both of Sale's tries, TMO Geoff Warren made the calls from the van parked outside the ground.
Cueto's touchdown had the crowd roaring their disapproval for a forward pass by MacLeod, while Forsyth's was referred for a possible offside by the centre.
Diamond added: "We got two tries which some people might think are contentions tries but if the ref gives it and the technical match official gives it, you can't say anymore than that. So I am happy with the result."
Gloucester head coach Nigel Davies was far from happy with the opening performance, which saw them at sixes and sevens until they got their act together in the final 20 minutes.
He said: "There were moments in our game when we creaked and didn't really give us control of that match. Both line-out and scrum were poor in terms of us getting our game moving from that starting point.
"At the end of the day, there were other areas - game management and the contact area - where we came second best and fundamental to our performance was the set-piece which we have to get right.
"I don't think we deserved to win it. We didn't have enough control of the game. The thing we have to do is lick our wounds a little bit. We are wounded, we are humiliated but that is the nature of the sport we are in. It is the last thing we would want here at Kingsholm."
Davies did not either use the TMO's decisions to award Sale the controversial tries as an excuse.
"I would say the second one was an offside from the kick but sometimes those calls go for you, sometimes they don't," he added.