Well, If you SCRoG them you could get 3-4 plants.
You say you have 300w of CFL's i'll asume you have 20-25watters so that's 12-15 light bulbs.
If you install a screen and grow them to fill the screen you could have a cfl every 5 cm and set them in a box-shaped pattern 3X5 or 3X4. I'm not in the mood to think in english so i'll just draw what i want to say.
I find CFL's almost as efficient as HPS . I am currently growing 3plants with a 150w HPS and a 20W auxiliary HPS( for some buds that don't receive full lighting ) they look good.
My first grow was 100% CFL but it looked better. I spread the light all over 1 plant though so i had like 180W of clf's for 1 plant.
The whole idea of this is to try to sprea the light evenly across the plant and most efficient. Put tin foil/mylar/whatever reflecting thing you have above the lights so they give everything to the plant.
Happy growing. Sorry for my weirdly structured message, i am tired.