In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: Why did using the method Bach didn't use, gain traction?, Context: The theories surrounding equal temperament began to be put in wider practice, especially as it enabled a wider range of chromatic possibilities in hard-to-tune keyboard instruments. Although Bach did not use equal temperament, as a modern piano is generally tuned, changes in the temperaments from the meantone system, common at the time, to various temperaments that made modulation between all keys musically acceptable, made possible Bach's Well-Tempered Clavier.

Answer: it enabled a wider range of chromatic possibilities in hard-to-tune keyboard instruments


Question: What needs consistency?, Context: The simplest valve gears give events of fixed length during the engine cycle and often make the engine rotate in only one direction. Most however have a reversing mechanism which additionally can provide means for saving steam as speed and momentum are gained by gradually "shortening the cutoff" or rather, shortening the admission event; this in turn proportionately lengthens the expansion period. However, as one and the same valve usually controls both steam flows, a short cutoff at admission adversely affects the exhaust and compression periods which should ideally always be kept fairly constant; if the exhaust event is too brief, the totality of the exhaust steam cannot evacuate the cylinder, choking it and giving excessive compression ("kick back").[citation needed]

Answer: exhaust and compression periods


Question: Who attempted to fix the formula?, Context: Despite the dominance of the above formula, there are documented attempts of the financial industry, occurring before the crisis, to address the formula limitations, specifically the lack of dependence dynamics and the poor representation of extreme events. The volume "Credit Correlation: Life After Copulas", published in 2007 by World Scientific, summarizes a 2006 conference held by Merrill Lynch in London where several practitioners attempted to propose models rectifying some of the copula limitations. See also the article by Donnelly and Embrechts and the book by Brigo, Pallavicini and Torresetti, that reports relevant warnings and research on CDOs appeared in 2006.

Answer:
several practitioners