You can be cleared for descent on the glidepath at LL from five thousand feet which ties with a range of 15nm.
CDAs are expected to be flown from minstack - usually 70 or 80 depending on high/low pressure. Hence the track miles given with descent below minstack. It's not practical in busy traffic from higher levels as minstack is used to ensure vertical separation between traffic off the stacks and traffic holding. And on easterlies off LAM/BIG you're sandwiched between departures and the BNN/OCK holds respectively.
That said, we will attempt to give continuous descent whenever possible.
Quick question - how does the 773ER cope with the 'standard' speeds on intermediate/final approach? 180 or 190 kts on base? 160 to 4 or 170 to 5, or does it depend on the weight on the day/SOPs?