If this is true, that's one good use of Singlish...
I recall doing the same in reservist too..
The Spore air force went to the US to take part in their Red Flag combat exercise.
For the first three days, our F-16 pilots, no matter how much they planned and prepared, they were always ambushed by the USAF F-15s. Then they realized that the USAF pilots were eavesdropping on their conversations (not disallowed by the rules), so they switched from plain English to Singlish/Chinese/Malay.
Suddenly the F-15s lost their magic, and for the last three days, found no way through the defensive screen set up by our F-16s.
So who says Singlish got no use har?