Typical plan 100-500
Typical complex plan 500-1000
Multi-year complex plan 1000-2000
I only go up to 500 maybe 600 max.
Anything larger, it gets too complex
to manage.
A 20,000 line project cannot be managed.
Additionally, the file will most likely get
corrupted in short order. All you need is a
hundred milli-second disconnect and the file
is toast. Hope you have backups.
The speed of a plan is a combination of
factors (grossly simplified):
(tasks) x (resources) x (duration)
A 500 line plan spanning 3 months
with 10 resources will load quicker
than a 50 line plan spanning 3
months with 200 resources.
Of course you need to add server
speed and sever load with network
speed, network latency and network
load. Oh and if you are going over
a WAN, or VPN, or VPN through WAN,
things will get even slower of course.