The Proteas booked their place in the T20 final with a brutal defenestration of Afghanistan and will now face India in Barbados on Saturday.
Walter is the antithesis of that 'high profile' coach -- he was never a star player, he stays resolutely grounded in interviews and if he is prone to outbursts of raw emotion he does not put them on public display.
Just one journalist attended his press conference for that semi-final.
The previous 12 South African white-ball coaches include such storied names as Mike Procter, Bob Woolmer and Mark Boucher and yet it is the 48-year-old Walter who has succeeded in shaking off the "choker" tag that dogged a side that could reach semi-finals but no further.
Walter said he believed the team had already overcome their biggest psychological hurdle.
“Getting through the semi-final, not having done that before, came with its own pressure," he told AFP.
"Even against the West Indies (in a crucial Super Eight match), that was effectively a quarter-final.
"Now that they've done that I'm just hoping the guys will go out, play freely and express themselves."
If they do that successfully it will be a significant triumph for Walter, whose playing career peaked at schoolboy provincial level and who had only been involved in coaching at age group level before becoming South Africa's strength and conditioning coach in 2009, a position he held in 2013.
The recommendation of previous national coach Gary Kirsten helped Walter land a job as head coach of the Titans, South Africa’s most successful franchise.
The team won three titles in three seasons, leading to head coach positions with Otago and Central Districts in New Zealand.
He was appointed South African white-ball coach in January 2023 and has brought a calm to the dressing room, although he admits that outward appearances do not tell the whole tale.
"I wouldn't say there aren't emotions deep inside but there's a calmness required on the side of the field," he said.
"Our job as coaches is to prepare the guys beforehand and make sure that everything's in place before the first ball is bowled.
"Once that happens we try to stay in communication with the captain but basically it's over to the players.
"I try not to get too emotionally attached to the result, more to concentrate on how we prepare."
'Very calm'
The results, though, have all gone South Africa's way with eight successive wins, several of them nail-bitingly close.
The only truly comprehensive win was against Afghanistan in the semi-final in Trinidad on Wednesday where the Proteas romped to a nine-wicket win after bowling out their opponents for just 56.
Walter has high praise for captain Aiden Markram, who he describes as "very level-headed, very calm," with a tactical astuteness that has enabled him to make crucial decisions under intense pressure.
Given that his team have played on untypical and unpredictable pitches, Walter said they would not have any pre-conceived ideas about what to expect in Barbados.
South Africa have some powerful ball strikers but they have a combined total of only three half-centuries in the tournament, two by Quinton de Kock.
But Walter is confident they will be able to rise to the occasion if conditions in Barbados are more favourable for batsmen, as suggested by earlier results.
"The batters have all contributed at different times. We've had two decent wickets for batsmen which in eight games is not a lot.
"The bowling unit has been unbelievably good but the batters I am sure are looking forward to better conditions."
If South Africa succeed on Saturday, there can be little doubt that Walter's low profile may not stay that way for much longer.
