Aside from bigoted violence and ignorant superstition, a serious pitfall of blind faith can be a dormant dependency on God while doing nothing for yourself or others. In fact Christian fundamentalists have a glib motto for such lack of moral and personal ambition, namely: "Not by works but faith alone".
First of all, this motto stems from a misunderstanding of Paul's preachings. In order to break away from Judaism, Paul had to also break away from strict Jewish law involving circumcision, food prohibitions, and elaborate rituals. Therefore he emphasized rebirth into a new covanant of grace not by works of the law but by faith itself. He said nothing about stopping good works and deeds in the world.
Reading Paul's Epistles, you will constantly see his admonishing works of the law - not works and deeds outside Jewish law. "One is not justified by works of the law but by faith in the Christ....For by works of the law no works shall be justified." (Gal. 2:16) (See also Gal. 3:13; Rom. 2:15, 9:32; Heb. 6: 1)
Augustine repeated this teaching in the early dark ages to discourage those trying to conjure Christ through magic. Luthor and Calvin did so to oppose benefices paid to the Roman church. But these men were discouraging what they saw as empty ritual, magic, or corrupt paractices meant to appease, conjure,or bribe God. Nothing was said of forbidding loving deeds or not actualizing the gifts given you.
"And the greatest of these gifts is love," states Paul. (1Cor. 13:13) "So let us consider each other in order to stir up love and good works." (Heb. 10:24). Therefore James states: "Faith without works is dead." (Read James 2:1-12. Also see Titus 3:8) So there is no longer a Biblical excuse to let your gifts go dormant or ignore those in need.
DEAD FAITH VS. ENLIVENED FAITH:
Understanding faith as not just positive attitude but as positive action is the key to making it work optimally for you and for others. Suppose you seek a healing. There are two ways to go about it. You could simply ignore modern medicine and pray. Or you could find the best medical attention possible - then pray. Only the most fanatical blind believer would consider the first choice more fruitful. (Jesus said, "There will be physicians after me.")
Likewise, if you are seeking an important discovery you could simply sit back and pray for it, or you could do the research till you get to the brink and can go no farther - then pray. The greatest discoveries came seemingly out of the blue, but only for those who first did their homework and hence knew what to look for.
And so it will be with any goal you seek. Remember Scripture states: Seek and you shall find. Ask and you shall receive. Knock and the door will be opened to you. But you first have to seek, ask, or knock.
"God helps those who help themselves," indeed.
Where then does blind faith come in? It comes in after you have done all you can to make things work - not before. In this way faith becomes more than a passive hope. It becomes instead an an alert vigil for the next opportunity after you reached an impasse at the brink of what you desire.