Reading looked dead and buried after a Romelu Lukaku doubled earned Baggies a deserved 2-0 lead going into the final stages of Saturday's Premier League clash at Madejski Stadium.
But Royals responded with three goals in the final eight minutes to snatch victory from the jaws of defeat and boost their chances of Premier League survival.
And McDermott insists Royals fans will rarely witness a more dramatic comeback.
"It's a fantastic result and I'm delighted," beamed the Reading boss.
"West Brom are a good side, Steve Clarke has done a fantastic job there but our first goal was key. When it went in the crowd really got into the game.
"I thought we had a major chance at that point and the crowd got us over the line. The real Reading was on show in the last eight minutes.
"Talk about any qualities you like and what we might not have - but we never lack desire, togetherness and a willingness to work for each other.
"That was as good a comeback as you're ever likely to see."
Reading looked the more likely to take the lead early on but West Brom weathered the pressure before Lukaku fired them in front in the 19th minute lead.
The teenage striker linked up well with James Morrison who drilled a cross-shot across goal for the burly Baggies' striker to tap in.
It took a lacklustre Royals until the 31st minute to muster an effort on goal when Jobi McAnuff's header was easily held by Ben Foster.
And when the hosts did create a clear cut opportunity in the 40th minute they blew it when a heavy touch from Kebe gave Foster the chance to clear when the Royals winger only had the keeper to beat.
McDermott opted for a more attacking approach in the second period by replacing debutant Daniel Carrico, who started in a sweeper role, with winger Garath McCleary.
And 10 minutes later McCleary was unlucky not to equalise when his first-time strike was blocked by Billy Jones in front of a gaping net.
Baggies, though, remained a threat and Lukaku almost doubled their lead on 57 minutes when his header crashed off the post with Adam Federici beaten in the Reading goal.
And he was denied by the woodwork again on 68 minutes with a rasping drive that rattled the crossbar.
However, it was a brief reprieve for Royals as the on-loan Chelsea forward grabbed his second of the game a minute later.
He picked up the ball 40 yards out, ran straight at Adrian Mariappa then hammered a left-footed shot inside Federici's near post from the edge of the box.
It was poor defending again from the home side, but to their credit they kept pushing forward and got their reward with an 82nd-minute lifeline.
Pogrebnyak found McCleary whose cross evaded everyone, allowing the unmarked Kebe to head home at the back post.
Suddenly, Royals began to believe and they were back on level terms six minutes through a clinical Le Fondre penalty after Kebe had been fouled by Jonas Olsson.
And the comeback was completed in the 90th minute when Alex Pearce flicked an Ian Harte free-kick to Pogrebnyak who lifted the ball past Foster from close range.
McDermott added: "To score three goals in eight minutes in the Barclays Premier League is phenomenal.
"We've been on the wrong end of a lot of high-scoring games this season and we don't want that. We want to entertain our fans, but most importantly our fans want to see us win."
It was Reading's second successive home victory in the Premier League after the win over West Ham and will raise their hopes of escaping relegation.
Reading travel to Newcastle United this Saturday (3pm ko).
Reading: Federici - Gunter, Mariappa, Pearce, Harte - Carrico (McCleary 46) - Kebe, Karacan (Le Fondre 65), Guthrie, McAnuff (c) - Pogrebnyak. Subs: Taylor, Hunt, Morrison, Cummings, Akpan.
West Brom: Foster - Jones, McAuley, Olsson, Ridgewell - Dorrans (Rosenberg 79), Thorne, Brunt (c), Thomas - Morrison - Lukaku. Subs: Popov, Ghanassy, Myhill, Dawson, Tamas, Nabi.
Referee: Kevin Friend.
Attendance: 23,495 (2,158 West Brom).