I never had any luck with a straining bag on my racking cane. BUT, I just kegged 10 gallons of beer today with 3 ounces of dryhops, and I didn't have any problem anyway. I start the siphon under the floating hops, but way above the trub, in about the middle of the fermenter. As the level of the beer lowers, I lower the racking cane. If I start to see yeast in the tubing, then I back up a bit. It works great, and never a clogged siphon!
Broken Leg Brewery
Giving beer a leg to stand on since 2006