Originally Posted by clayof2day
Plus the trub is suspended in the wort, not dissolved in the wort so it should not affect SG. A log floating in water does not affect the density (SG is a measure of SG).
Hydrometers are used routinely to measure suspensions (ie the amount of clay in silt etc) so i don't think particles need to be dissolved/solvated to cause an increase in the hydro readings.
Also you could argue that the larger trub clumps (those likely to fall out out much quicker) are less likely to keep the reading high as apposed to the much smaller particles which truly are in suspension and therefore take a long time to come out of it (overnight).