In Final Fantasy 13-2, when you choose to upgrade the number of ATB slots you have, does this have any affect on the charge time? Does it remain constant(resulting in a longer amount of time to load the full bar) or does it increase at all?
From some experimenting i did myself a atb bar with 3 slots takes about 4.3 ~ 4.4 seconds to charge. increasing the amount of gauges incread the times a little but not by a significant amount +- 0.2 seconds.
Here's a table of my findings
To answer your questions:
Yes upgrading the number of ATB slots does increase charge time. But at 6 charges you pretty much have an efficiency of around 180% compared to the charge speed at 3 slots
to confirm, here are my recharge averages:
ATB level | full recharge | recharge per bar
3 | 4.32 | 1.44
4 | 4.46 | 1.11
5 | 4.66 | 0.93
6 | 4.79 | 0.80