I honestly don't know why anyone would try to filter pellet hops. A simple whirlpool works quite well and the little amount that makes it into the fermentor is nothing to worry about.
I may try this. I tried to whirlpool on this go around but I think the Hop Blocker disrupted the flow. I've been avoiding whirlpooling as the only method because it takes so long to flush the plate chiller until no hop particles come out. But the bottom line is I just don't want the chiller to plug.
I know Denny and others really like an immersion chiller. I don't. It takes too long and the cool wort is exposed to airborne bugs and wild yeast. Admittedly the chances are remote of this being the cause of a spoiled batch, but I think it is best to remove all possibilities. Its a basic QC issue: identify critical control points and eliminate the possible hazard.
In true Denny fashion I'll just keep experimenting until I find what works for me on my system the best. I guess $60 wasn't a bad cost for an experiment.