The way I see it.... the only time Blockers are dangerous to consider is when we are playing limpy, limpy, cally, cally, style games that have 3-5 way pots everytime.... but even then we should consider them when making river calls, and trying to bet turns and rivers....
I dont know about you, but I dont bloat pots in these type of games unless I know I should be getting it in on the river in most run outs.... if that's the case chances are by the time you blocker comes into play the pot probably isnt that much for it to be a huge stack diminishing decission.... so for my census on this subject, you should always be considering them, and not be resualts oriented.