That's the only reason I can think of why Armour has no Malays... comments?
Yours is but a brief summary of our supposed "pre-emptive offensive" - i.e. electronic warfare (ADSD), air superiority (RSAF), amphibious/heliborne inserstions to secure bridgeheads (CDO, RDF, RSN), then rapid ground advance (SAB, RDF, SIB) - to a theoretical "Mersing Line", thereby safeguarding the water-pumping stations as well as buffering the island from arty range, prominent communalist agitation & economic leverage.
The idea is to starve off another Jap-style operation in reverse, but the whole blueprint is so common sense that generations of staff officers must've gotten promotions from such campaign designing ~lol~
More soberly, the SAF - even LKY himself - seriously wondered within context about the commitment of local Malay &, let's face it, also other Muslim & perm resident servicemen. Hence the traditional reluctance to post them with such vanguard forces &, to some extent, ditto the ongoing institutional distrust. The stakes are just too high.
That said, it's by no means the whole story; IMO the relationship also involved other serious, complicated variables:
1stly, the SAF faced bigger grassroots problems with initial conscription. In particular, banishing the Chinese culture prejudice about soldiering (vital cuz they formed the bulk of NS intake) & professionalizing training/safety standards to assuage familial concerns. I don't think either achievement was truly realized until the early '80s.
2ndly, the SAF's early marginization of Malays - from "declawing" regulars to shelving conscripts ('69-73) to restricted combat postings (post'73) - was retrospectively controversial, but quite unavoidable. There was a need to remix the ethnic balance militarily, amid deep suspicion about local loyalties from the Malay communalist threat. Yet I don't think this was a longstanding difficulty - as often made out to be - compared to another inadvertent development: the economic dislocation & general alienation of an entire community.
The Government's chosen remedy is to initially stem the societal problems (like drug-taking), then attempt to reintegrate the Malays back into the civilian mainstream (via affirmation programs), while
concurrently opening up the military to them again. In other words, the latter-duo approach is mutually inclusive of each other, rather than relate on a causal basis. IMO It's gonna take at least another decade, except I think a new variable could perplex things (more on that later).
3rdly, the SAF also serves a nation-building platform, not just defence. Propaganda, physical fitness, academic & skills courses, common bonding et al. were/are daily experiences of positive reinforcement. Yet its internal social mores are very resistant to social engineering, which meant that Malays - already in perpetual catch-up mode with full-scale enlisting from '85 - had to assimilate into a core culture that doesn't "wait" for them. A highlight would be the Hokkien-Singlish lingo, which has survived bilingual education ("proper" English; Mandarin vs. dialects).
4thly, the lower national birthrate (post-'80s) forced a SAF rethink of manpower resources, regardless of race. Yet, throughout last decade, it has exponentially "technologicize" the soldier profile as well as the weapon systems, both for a force-muliplier edge & also an end in itself. This has its plus points but also created new conflict perceptions: scholars vs. farmers; managers vs. leaders; ops needs vs. training realities; confidence vs. British/WWII-style overestimation, etc.
With the Malays, even as they close the gap on the educational front, I wonder if they'll find the military-technocrat mindset a new barrier.
5thly, I don't foresee eventual combat postings as potentially delicate. Some postings will be off-limits - necessary evil for living in SE Asia - & special forces like the CDO has their own enlistment criteria. But the general mono-intakes (as base for combat main body) for SAR, SA, SCE & some GDS elements won't deviate from a blanket-encompassing nature, esp. since their units form conventional brigades that come under a combined-arms DIV.
The more intriguing question, I think, is who'll take the transplanted Malays' places in the Police & SCDF paramilitary forces. Women? Newer/older/1st-generation perm residents?