BOAC:
How should it be flown to stay in the terps zone?
In those circumstances it is not possible to remain within the inadequate TERPS circling airspace. That's why those of us who are honest brokers have tried so hard for at least 15 years to get far better CTL criteria in TERPs. But, thus far, the special interests are prevailing.
There are a couple of work-arounds that work at some locations.
1. Get a copy of the FAA approach chart to determine if the airport has Approach Category E CTL minimums. (Jeppesen doesn't chart them). If the location does, then use the CAT E MDA and accept any weather minimum penalty that results.
2. At locations without CAT E CTL minimums an operator using aircraft that bump up against the CAT D limits are well-advised to conduct their own flight-track analysis as to whether it is safe to breach the 2.3 mile containment area. Often, there are no obstacles where it could bite. But, "often" is far from always.
The option to slow the airplane down to a potentially unsafe airspeed is simply not worth the risk.
And, circling is a very high risk option at night or in precip without a thorough airport assessment by the operator and without meaningful training in all aspects of the CTL maneuver.
Then, there are the even worse traps at high elevation airports, and especially those with CTL MDAs well above standard.
For-hire performance engineering vendors could provide some great services in this area. So far as I know, none of them do that.