Assuming level 60 and no misses. The relative damage remains the same as the miss rate is going to be constant over time.
If the floor is 5 then thats 15max damage per hit (weapon dmg *2 +11) every .5 seconds. If you have pretty much any haste you'll hit the floor(fbss will do it). So 120 attacks per minute.
15 * 120 = 1800 DPM = 30 DPS max without double attack.
http://wiki.project1999.com/Rod_of_Faith 24/32 is 59 max dmg per hit. with 100% haste (Sky belt + high level enc haste will hit the 100% cap) gives a delay of 16 so 37 swings per minute (rounded down).
37*59 = 2183 DPM = 36.38 DPS max without double attack. RoF out performs the blade by ~17%
Paladins double attack approximately 56% of the time.
So the 120 attacks with the blade would be 187 attacks.
The 37 swings with the RoF would be 57 attacks.
15 * 187 = 2805 dpm = 46.75 dps
59 * 57 = 3363 dpm = 56.05 dps
All things being equal the RoF would outperform the bixie blade by 17% with max haste still.
In a no spell haste situation (just using 41% sky haste) the bixie blade would perform no differently but the RoF would lose a significant amount of effectiveness.
27 swings = 42 attacks after double attack.
59*42 = 2478 dpm = 41.3 dps
So in a situation where no magical haste is available the bixie will always win.
At approximately 65% total haste the RoF is pretty much equal to the bixie. Any haste beyond that causes the RoF to pull away.
This is assuming the 5 delay floor.
Without the floor the bixies max DPS potential would be
15*312 (200 attack rounds, 312 after double attack) = 4680 DPM = 78 DPS. If the floor exists, it massively nerfs the blades potential.