This paper, C. Gabrielli, R. Jaouhari, G. Maurin and M. Keddam, Magnetic water treatment for scale prevention, Wat. Res. 35 (2001) 3249-3259, that was referenced in this link http://www.lsbu.ac.uk/water/ref3.html#r259 of your first link, states this:
'Many tests mainly utilizing single pass systems, however, have proved negative . Recirculatory systems, with prolonged magnetic exposure, give more supportive results. Rapid movement (1200 rpm) in a strong magnetic field (4.75 T) had a significant effect compared with the movement or field alone '
'This study also showed an optimum in the flow rate as at too high a flow rate the magnetic field was encountered only briefly, an effect recently confirmed . Recently, the presence of dissolved oxygen has been shown important for the production of the magnetic effect for forming aragonite rather than calcite , and for initiating scaling . It may be assumed that many of the studies described on this page did not control for oxygen content, so their effects may have been moderated by the varying dissolved oxygen contents.'
And Ill let you, mister inflammatory, tell the rest of the audience why dissolved oxygen might be important for this effect (I'll give you a hint: it has to do with oxygens molecular orbitals and where its last two electrons reside in the ground state (ill give you a hint at what the ground state is: its not the excited state!)).
Heres also a statement from YOUR link for clarification of exactly the claim of these systems do for anyone out there who still needs clarification on this:
1. Reduction in the amount of limescale formed.
2. Production of a less tenacious limescale due to a change in the crystal
3. Removal of existing scale (3 - 6 months).
4. Retention of anti-scaling properties for hours following treatment.
*NOTE: does NOT claim to remove the hardness*
From the words of your author on his own webpage: 'For some users, MWT seems to be effective in controlling scale deposition; there are too many favorable anecdotal reports to dismiss it entirely.'