Hi all. My first post , but I've been lurking here for awhile now. Anyway, I though I'd put my two cents in on this.
I find this unlikely. While the Heralds were probably named after their heralding of the desolations, they must have certainly been incredibly powerful in combat: Even though originally there were no spren-bonds, and so the only source of surgebinding was the Heralds, it is apparent that humanity survived the desolations. If 10 Heralds + conventional armies were enough to at least survive a desolation and Radiants are indeed more powerful than heralds, than one would imagine that 10 Heralds + (presumably) hundreds if not thousands of Radiants + conventional armies should have easily defeated all desolations that came afterwards without too much trouble (although I must say, now that I think about this, I somewhat question how they ever survived the first ones).
I must say I had originally agreed with the OP, but I think I like this idea better. As we know from a WoB, Nightblood is also more powerful than a regular shardblade, so it makes sense that extra draining of investiture gives extra powers. Plus, as Vaspin already referenced (yet strangely got the opposite conclusion), we have a WoB that one Herald went back to get their Blade. If the bond wasn't broken then they wouldn't have to go back to get it, they would just summon it to themselves (although I can't find the quote, so my wording could be wrong).
Well, as to this, in the prelude, Jezrien does strongly imply it:
This was not 'should be left', nor was it 'we will leave our blades and go our seperate ways'. Right after saying things that they would do, he says something they must do: it seems to me that the choice of wording was purposeful. Hence it seem unlikely for it to be for symbolic reasons. Moreover, even Syl could figure out that the Honorblades are dangerous if they get into the wrong hands. If the Heralds wanted to help humanity out by leaving the Blades, then just leaving them in the middle of nowhere is a pretty bad way to go about it (after all, it did lead to Szeth murdering who-knows-how-many people). I would think the Heralds would realize this, and give them to people they know would use them for good (such as the Radiants).