"Descent" made it clear their invasive program wouldn't work. Thus if anything Picard was right for not doing it because doing so would've just provoke the Borg into a REAL invasion mode and doomed the Federation.
The borg were ALREADY in invasion mode against the Federation.
You see - one can't be sure that the klingons/romulans/dominion will start a war.
But one can be absolutely sure that, once the borg marked you for assimilation, they WILL come for you.
Because the borg hive mind doesn't have a true free will - it just obeys its impulses - that blind 'will to conquer', to assimilate - , which makes its actions largely predictable.
The borg coming for the Federation was as certain as the sun rising next morning. Anyone who thought otherwise were just deluding themselves -
and showing poor medium/long-term thinking/planning skills.
Why didn't the borg already came in masse to assimilate the federation?
Because Starfleet stopped them in 'Best of both worlds'? RIDICULOUS! The borg have HUNDREDS OF THOUSANDS of cubes (the number usen in 'Scorpion' is actually MILLIONS of cubes; I'm being conservative)! What happened in 'BOBW' barely qualifies as a skirmish for the borg.
Guinan, in 'Q, who', explained why the borg didn't already come - the collective doesn't do anything hurriedly; it always takes its time.
The cube in 'BOBW' and 'First contact' were on reconnaissance missions. By 'Dark frontier' the Queen was planning a somewhat larger attack - let's say, 1000 cubes (a smallish force by borg standards).
Tell me - what chance would Starfleet - and all the BILLIONS who live in the federation - have against 1000 cubes?
As for the borg - Data/Geordi know in detail the Federation findings regarding borg technology (gathered in 'Regeneration', 'Q, who', 'Best of both worlds', 'I, Borg') - including, but not limited to sensor scans, borg implants analysis, Data/Locutus having access to the borg hive mind, etc.
Is this knowledge complete? No
Is this knowledge FAR more detailed and complete than the ridiculous superficial knowledge we have of borg tech? Yes
And yet they didn't know about the Borg being able to cut off drones that have been infected with some type of virus like the poster above mentions.
Who said the borg will be able to counter the logic paradox by separating infected drones?
Who said Picard&co didn't knew about this borg feature?
Perhaps Picard&co were so jaded when it came to the individuality program because they knew about this borg feature (or others along the same line), just as they knew it would be effective in stopping the individuality attack.
In any case, in their attitude one can clearly see that they think the individuality attack has very low chances of success (unlike the logic paradox). And they were right in this regard.