I think, before the 'discussion' slips any further, that perhaps we ought to get people to clarify what is important to them and why?
While a bollard pull may be a factual and accurate method of measuring the available "thrust" from a particularl engine/prop combo, and providing all other factors (same boat, same tide, same weather, same fuel, same air temperature and density...) are identical, then one would have merely established which has the greater or lesser "measured bollard pull".
So if one required a vessel and motor capable of a higher bollard pull - say for towing a barge - then that might indicate which motor/prop combo to go for.
But if, as Charlesuk has pointed out, one is after "forward speed throough the water" then a bollard pull is not a real indicator of that.
It's all about the gearing and the pitch, but the lower gearing provides for less revolutions, ergo the larger prop with lower geared box is going to travel slower going forwards than the hydrofan on a similar cc motor with a higher ratio gearbox. Smaller thrusts, but more of them, more often.
It is for the same reson that trucks have lower diff ratios than sports cars, and why, in my long ago squandered youth we swapped out the 3.37:1 diff in the old Holdens for a 4.11:1, as it lowered the back axle ratio and allowed more power to be put on the ground, making the car accelarate harder and faster, but it was ultimately slower at top speed, revving much harder to attain the 100km/h than before.
Au contraire, if one wanted lower revs at highway speeds, say for improved fuel mileage, one swapped out the standard 3.37:1 for a 3.08:1, as this allowed the back axle to spin faster for the same engine revs.
Outboards operate on the same principle. Energy in = force out. Gearing determines where and at what point in the rev range the force comes out.
Hope that helps!