Just to follow. As I said I would.
On surface pro 4 I5 8GB integrated gfx
to cut a long story short as it looks like it is accepted and yes I have confirmed above.
YES, 1000+ real events with actions fully expanded on one sheet causes lag of maybe .5 seconds opening events and maybe up to 1 second when moving bits of the editor.
however collapsing them and only expanding and opening events per group then there is no lag.
so it seems to be about expanded events.
But, not to lecture anyone, but IMO 1000+ events is an insane amount of events to have un-grouped or on one 1 sheet un-grouped just from an organisational point of view. It must make it near impossible to navigate your project code efficiently.
anyway regardless, from what Ashley said it looks like things will be getting even snappier with future updates of chrome so cool.
(man I am so doing anything to avoid going back to my project from after Christmas.... need to get that discipline back)