This phrase (in various variation) was really used in early 1920s, but without reference to Lenin, and there is no indications that he really said it.
Hi Art, I think you may be missing the point. I think we all agree that Lenin may or may not have said it. However, the fact remains that the phrase (and its variations) emanated from the Soviet Union and not 'patriotic' Poland.
Your argument about Tukhachewski's order would be more convincing if the phrase
The road to worldwide conflagration leads over the corpse of White Poland.
wasn't immediately followed by:
On our bayonets we will bring happiness and peace to the working (?toiling) masses.
Even if T was being deliberately disingenuous, it is not unreasonable that most folk would interpret this statement the way they did and do. On a wider issue, even if we can't prove beyond doubt that some of the other statements I have quoted were really said by the people they are ascribed to (a problem with all oral statements recorded by others) the sources are not 'Polish patriots' but Soviet, British and German observers/commentators.
On the wider question, however, I think Art is correct. There was no agreed detailed plan as to what the war aims were and the plan evolved, as most war plans do, as the situation developed. However, while finishing the war ASAP was a priority, so was the spread of international communism/socialism (without going into the detail why) and if events had progressed in Poland as the more optimistic Soviet Leaders had hoped, I see little reason why the Red Army's advance would have been halted until it was stopped - either by military action or a very convincing show of force (and the latter only a factor if the view prevailed in the Soviet leadership that it was 'not enough to wave a red flag' to mobilise the workers to overthrow their government).