What type of conditions?
Wet?
Dry?
Steep?
Rooty?
Loam?
Hard pack?
Need more info.
I'd say wet, steep and rooty. If it can handle those , it should be able to handle the drier hardpack stuff.
I think of the first part of the Powerhouse Plunge. rooty, wet,
I like Schwalbe tires in the front. I'm using a Little Albert right now, but have a Fat Albert as well for my wife's bike in the drier months.
They roll well and have a lot of grip - a lot of trials riders use these tires.
I have hear good things about the Alberts
Also the Racing Ralph's for rollability.
I've run the Jimmy Lights and they seem to be too low a volume tire and not sticky enough.
Nobody's mentioned the Nevegal? 2.1 UST in the back with a Blue Groove up front? That combo usually sits at or near the top of most xc tire shootouts.
I have the 2.35 Stik-e. sweet for confidence. They don't roll very well though.
Coasting down a paved hill. I've found some tires stick to the road like glue and suction cups( slowing the bike down), where others keep the bike accelerating.