First of all, you don't seem to understand exactly what a "class struggle" is. A class struggle is precisely that, the struggle between classes. A strike is just as much a part of class struggle as the take over of a factory.
Second of all the bourgeoisie does not have the power to do "just about anything". Capital cannot survive without labour. It needs labourers to create surplus-value to expand itself. If the bourgeoisie really could do whatever it wanted then even strikes would be utterly futile since they could just starve the striking workers.
Thirdly you don't seem to understand what "class collaboration" is. "Class collaboration" is when the political independence of the working class is sacrificed and the workers movement is subordinated to the interests of another class, usually under the pretence of winning "progressive" goals. National liberation is an example. In natlib struggles the political independence of the working class is sacrificed to the interests of the national bourgeoisie in order to fight Imperialist occupation. In your example of a strike, the workers are acting as an independent force in direct antagonism to the bourgeoisie. This is a form of class struggle, not collaboration.
There is no "middle path" between struggle and collaboration. Either the workers and capitalists work together for some common goal or they struggle for antagonistic goals. And for the most part they struggle since everywhere the interests of the workers are in direct conflict with the interests of the capitalists. It's just a matter of how far these struggles are taken.
Most social-democrats and those within the workers movement who refuse to confront the question of the capturing of power by the working class are engaged in a futile sisyphian struggle. Today you might win an immediate victory, but tomorrow the bourgeoisie will have found a way around it and the struggle will continue. Communists link the immediate aims of the workers movement to a greater picture of the historical road the workers will need to take. That is, the abolition of the class struggle by the capturing of power by the workers and expropriation of the bourgeoisie.


