Hi Fred
The wording of the relevant rule is:
4(e) Only one intercontinental departure and one intercontinental arrival permitted in each continent except as follows:
1. Two permitted in North America.
2. Two permitted in Asia.
3. Two permitted in Europe/Middle East for travel to/from/via Africa. If travel is to/from Europe in both directions, itinerary may not include Mauritius/South Africa
Your proposed itinerary is allowed under exception 2.
- It starts with an intercontinental departure (NRT-MEL)
- Followed by an intercontinental arrival (MEL-DEL)
- Followed by a second intercontinental departure (DEL-DOH)
- Then towards the end, a second intercontinental arrival (USA-SEAsia)
The rule is silent on stopovers/transits (old versions used to restrict stopovers). Because Asia is your continent of origin you are allowed a maximum of two stopovers there, which you have (DEL and somewhere in SE Asia).
Happy travelling Fred