Furtwangler was desperately disappointed that his music did not receive more recognition. He took his compositions very seriously and poured so much of his musical essence into them. Trouble was he he really know how to stop doing so ;D
Furtwangler's Symphony no. 2 is a fine work and undoubtedly the most accomplished of his three symphonies. The superb recording by Barenboim and the Chicago SO shows just what wonders a world-class conductor and orchestra can do with an obscure work :)
Meh. I listened to a couple of his symphonies on CD once, long ago. I can't say they fired in me any desire to return for a second look. Perhaps in another year or three...