HLS network stream download throttle in version 2.x but not in 3.x ?

[jeffl]

for the same HLS network stream which has segment length of 6 seconds
when using 2.x player it seems to throttle itself to download each 6 second video segment over 5 seconds
when using 3.x player it seems to download near full available bandwidth in my case under 1 second to download a segment.
is this intended? can you please comment on this behavior as it would seem the 3.x behavior would be better however it would seem that 2.x behavior would be harder to code so it must serve some purpose.
when the player throttles as in the 2.x it seems like it is more likely to fall behind when any packet loss or sudden larger byte sized segment is encountered.
any insight into the algorithms would be appreciated