Mouneimne left the club for personal reasons in the late autumn, but - after the 48-0 rout of Benetton Treviso last weekend - Edinburgh have now gone 225 minutes without conceding a try which Fife believes is a result of the systems the South African put in place.
And with Sam Hidalgo-Clyne and Tom Heathcote striking eight successful kicks from nine between them, things at Edinburgh are rosy according to the 24-year-old Scottish international.
"That's three wins from our last three games, and hopefully with each one we have been getting better," Fife told the Edinburgh Evening News.
"It was amazing to get six tries and a first bonus point since beating Connacht at home last season. But the boys are even happier at the clean sheet.
"Losing a defence coach is hard but it has almost brought us closer together.
"The boys are putting in extras and defence does win you games. We are seeing big hits and turnovers regularly now.
"Omar was a big loss, but I'm sure he is still looking at how we are doing to see how we are putting into effect what he taught us.
"When Sam and Tom step up that obviously lifts us too. We can always look back on things to work on which is good, too, but going 48 points up is always acceptable.
"Also, when you go ahead with a try after 45 seconds, as we did, that put heads up and we never seemed to look back."
The result was Edinburgh's largest victory in five years - surpassing the 62-13 rout of Connacht in 2009 - and more importantly keeps the momentum going heading into the massive back-to-back derby fixtures with rivals Glasgow Warriors, who they have not beaten since 2011.
The first game kicks off at Scotstoun on Saturday, and Fife admitted the games were vital in terms of selection for Scotland's squad for the Six Nations.
He said: "Scotland's coaches will look at Saturday's derby almost like a trial match.
"It is not just this game, other games get you noticed as well, but it is very important and I was sorry to miss out due to injury last year.
"Previously, I have only ever come off the bench at Scotstoun but on the occasions I have faced Glasgow I've found the level to be close to Test standard in intensity.
"We've been saying for some time we were due ourselves a big win and while Glasgow will definitely fancy themselves, especially with a vocal and sometimes pretty hostile crowd behind them, don't underestimate us now."
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