Yes, why not?

Oh dear where to go with this thread. SQ made an error by being impatient and ordering the fuel tanker A345 instead of waiting a few years for the 77L. The Worldliner had much longer range, TWO engines that are much more powerful than the four the A345 uses, and consumes 16% less fuel. The Worldliner can do EWR-SIN with what SQ wants. It might even be able to carry some cargo! But still, the 77L does burn up the same amount of gas the 77W with much less people. Its been rumoured SQ will be the next or one of the next 777X customers. The ME3 have ordered both the 777-8X and 777-9X. The 777-9X will have the range to do SFO-SIN under a normal layout. LAX-SIN would require restrictions and EWR-SIN not possible. The 777-8X will be closer to a 77W size than the Worldliner and already has a planned range of an astounding 11,000 miles. It can do EWR-SIN in a normal configuration, although not sure who would want to do EWR-SIN in Y. If its all J again, it can carry more in J this time and definitely some cargo. LAX-SIN can be done with a full load, at a much cheaper cost than flying a fuel tanker. The reason why the 777-8X will outsell the Worldliner is its much bigger, making ultra-ultra long flying cheaper. I'd be very surprised if SQ doesn't buy both variants of the 777X by decade's end.

There are still definitely people will do SIN-EWR on Y especially when it comes from once own pocket

People do DFW-SYD in econom, thats 10 min shy of 17 hours. SIN-EWR is only 2-3 hours longer.

Fifth-freedom rights are granted by formal written agreement either between the country granting the right and the country of the airline(s) involved OR between the country granting the right and the airline involved.

Either way, the formal agreement would either provide for forfeiture of the route from non use or be silent on it. If silent, I know of no reason to assume that the right no longer exist.

Has anyone read the agreement in question?

Absolutely.

But would the more price sensitive segment be prepared to pay a premium to fly SQ non-stop in Y?

The only aircraft I can imagine where SQ could afford to offer Y for EWR-SIN is the 778X. Keep in mind Y on the 777X is ten across but 18 inches wide. I'd imagine for a flight like this SQ might offer nine abreast, roughly the same as Executive Economy back on the A345.

I think the price sensitivity comes from who pay for the fare.

Most people who fly on J especially on long haul, most likely is being paid by company. Hence time is more important.

When SQ introduce SIN-EWR nonstop, it sheds 4 hours which is 8 hours both way (1 working day).

If you pay from your own pocket, typically you will be able to tolerate longer journey if it makes significant savings.

I fly between SIN-NYC 3-4 times a year. Given this is personal travel, I pay for these flights myself.

Worth noting that it's not only the duration of the journey that matters, but also departure and arrival times.

For example, just booked SQ in J JFK-FRA-SIN for next month, as the departure time maximises my day in NY and I arrive in SIN in time for a day in the office.

I don't have an opinion on either side of the question. I just wondered if SQ would go against BR X: TPE because TPE has lower demand/ traffic then other routes SQ flies parallel to a fellow *A airline ie: TYO-LAX, ICN-SFO, FRA-JFK.

Executive Economy on the original A345s had 7 abreast seating (2 - 3 - 2).

Don't forget HKG-SFO.

SQ used to operate SIN-TPE-LAX and dropped the TPE-LAX leg.

What about a fuel/technical stop? Seems it would add about an hour or so to the flight at fairly minimal discomfort to passengers?

Wonder why the non-taiwanese airlines (MH/SQ) all dropped LAX-TPE route, seems high profitability given the ungodly number of flights between CI/BR on a daily basis... (flown on all 4 airlines on this route). Granted, SQ had an accident in the 2000's, but MH dropped the route even before their issues.

One outside-the-box idea would be to tech stop in ANC and clear all the pax into the US so that upon arrival at final destination the plane arrives domestic -- similar to what BA does with the LCY flights via SNN

Obviously this is more feasible the smaller the airplane they're using...