Tim,
The Buffer is only useful when you want some task bars to "bleed" from just beyond the edges into the current time range. This would be useful if you have setup custom task templates that render tasks a bit outside of its time range - with some custom annotations, etc.
Now, if Buffer is set, then the Gantt would end up rendering more tasks than without and so entire load/page/scroll performance will go up.
And while paging/scrolling Gantt doesn't really reuse any of the already rendered tasks which is what you might have assumed (we understand, the property name might be a bit misleading, apologies for that).
Thanks
Praveen
