I'm tardy to this party but I think we (me) are bad at describing time speed. If I stood still and everyone else went fast, I might describe that as time "sped up" but I'm the slow one. Luckily, Brando solved this with sliders and pulsers. However this might be a dangerous description for future use... because cosmere. So I'll add astericks for now.
Correct me if wrong. Roshar is caught in a [pulser's slowness bubble]* while the heralds, whose minds are in the spiritual realm, are in a [slider's speed bubble]*
*not actual Scadrian magic.
Kadalin has said this first line as if he's in a pulser's slowness bubble.
and then this second line would indicate he's in a slider's speed bubble. Think of Wayne with all his spare time to change clothing.
I think this is the confusion with Kaladin's comment. It's contradictory.