Seajet
...
I know very little about Hiabs, but we did recently have our 'new' old boat moved by a lorry with a Hiab. From what I was told then I would think there would be no trouble lifting your boat.
The driver told me that the Hiab could actually lift 8 tons on the lorry bed itself, but that he couldn't lift a boat of that weight as the Hiab couldn't take amount of weight at the extent needed to place a boat that size on the ground and clear of the lorry. He said that 5 tons was manageable, and 4 tons was easy. He demonstrated this by lowering our 'new' old boat (design weight 3.4 tons, assumed maybe really up to 4 tons) at right angles to the lorry.
Little Sister,
not so sure about that; most cranes have a strain guage / load cell nowadays, and owners of supposedly modest 20-26' boats are often astonished at the weight reading.
There is the story of Uffa Fox having loads of heavy kit removed before racing a boat, and every year I vow then fail to 'keep her light' resulting in an amazing number of carloads to get all the kit backwards and forwards.
My boat is meant to displace 2,500lbs, and while weight can be a good thing to windward I've always thought it a suspiciously round 1970's sort of figure !