Well, the problem with basing a poll on that debate is that much of that debate is based on invalid definitions. The only full-on crossover Trek Lit has ever done is Destiny. Most of its "crossover events," including the current Typhon Pact, are really groups of standalone novels linked by common themes. They're specifically designed so that any book within the "crossover" can be read on its own without the others.
And they don't derail ongoing plotlines. In Gateways, for example, there were two series involved in the crossover with ongoing plotlines, DS9 and New Frontier -- three if you count Challenger, though that was only the second and final book in that "series." And in all three cases, the Gateways installments tied in far more strongly to the series' own ongoing plotlines than they did to one another. Yes, Demons of Air and Darkness involves the DS9 crew dealing with the Gateways crisis, but it's mainly a backdrop to the ongoing situations that are continuing from the previous books. Yes, "Horn and Ivory" results from Kira stepping through a gateway, but it's a very personal story deeply rooted in Bajoran history and Kira's own character arc. As for the NF installment, its connection to the overall Gateways crisis is rather indirect, with the antagonists supposedly connected to the antagonists in the other books but being rather different in their portrayal and actions. It's much more driven by stuff internal to NF than it is by the Gateways situation. And the Challenger book is only peripherally tied in to the rest.
And I question whether it's valid to say that even Destiny derailed any ongoing plotlines. In TNG, the various crew shakeups all took place in books set before and after Destiny, not during the trilogy itself. And Beverly getting pregnant (something which happened in Greater Than the Sum but was conceived -- so to speak -- during the development of Destiny) was not a derailing, but a logical progression of the Picard/Beverly plotline. As for Titan, Riker and Troi were already trying to start a family before the trilogy, so again it's a logical progression, not a derailing. True, a rather major change happened for Tuvok, the loss of his son, but arguably that fits neatly into his ongoing character arc in the series, augmenting it rather than derailing it.
Now, it's been argued that bringing Titan back to the Alpha Quadrant derailed its storyline of exploration in deep space... but 1) that's not a storyline, it's a premise, and 2) Titan was back in deep space again by the very next book after Destiny, so in the long term, nothing was derailed.
As for Voyager, the events of Destiny constitute a fairly small part of the storylines of Full Circle, doing little more than killing off a few minor supporting characters who would probably have been written out some other way anyway, as well as providing a justification for a return to the Delta Quadrant, which would probably have been done anyway, and which could be said to be putting VGR back on the rails it's been off of for years.
Although a case could be made that VGR was "derailed" by the death of Janeway in a TNG novel. I suppose that falls into the broad, non-"event" definition of a crossover, but one example doesn't make a pervasive pattern. There's also the decision to bring DS9 forward five years to sync up with the post-Destiny timeline. But those are the only cases I can think of where the progression of one book series has been substantially affected by events in a different book series. Generally, even when characters and concepts do cross over, each series follows its own path.
