no, for three gallons it did not produce an overpowering heat. just some spiciness on the finish. almost everyone who tried it thought it had a decent bit of heat and kick, enought to make them go "whoa", but not overpowering. it doesnt burn and its nowhere near as hot as tabasco sauce. There were a couple people who tried it who do not like ANYTHING spicy at all, and it was too spicy for them.
So if you are making a 5 gallon batch and you add 1 sliced habanero it should be almost half as spicy as mine, since I made a 3 gallon batch. If you are nervous about getting the right amount of heat, split the batch into two three gallon carboys and try two different amounts one bold, one less bold.