Is the investment strategy in 'Rich by Retirement: How Singaporeans Can Invest Smart and Retire Wealthy' by Joshua Giersch sound?

I believe it can work as the economy will go up in the long term. So by staying diversified and constantly investing, you will be able to retire rich through the power of compounding.

It's a strategy that is good enough for most people who want to invest. Although, you will only be able to get the returns that the market gives you since you're buying ETFs that track the performance of the various indexes.

If I not mistaken the allocation for local STI is 40%, personally think this is too high for me hence I adjusted it to 20% and added REITS for local exposure.
I think it's a good start for DIY 3 funds portfolio despite many say this method may not work in Singapore.

Cons:

-bonds have lower performance and maybe growing default risk (at least corporate bonds)

-STI index is a longterm underperformer

-U.S. passive indexing ETFs (like f.ex. VOO or IVV, or global VT) are excellent longterm performers

see here a 10 y performance chart (distributed dividends not included) of all your mentioned examples, SP 500 leads :-)

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