user11: Mainly referring to this question: Which voltage regulator should I use? [on hold]
Currently it's put on hold (by me) and has 3 re-open votes from the community so it's obviously worth a discussion to determine what direction the community wants to take this SE in.
The fact that it's an Arduino clone is not relevant to the question. The question is what voltage regulator should I use to get the most out of this battery while still being able to supply X volts and Y current.
When phrased this way, it's obviously off topic. But why does it become on topic if I mention the board I'm trying to power is an Arduino? Take a look at the answers to both Arduino.SE question and the EE.SE question. None of them mention Arduino, at all.
We've had a couple of other discussions regarding other topics but they all have the same theme:

Are questions about serial communication using third party software on-topic?
Are questions about IDEs other than the official IDE on-topic?

My policy is this:

Ask "What does this have to do with Arduino?" and if the answer to
  that question is not significant enough, then the question is probably
  off topic. https://arduino.meta.stackexchange.com/a/52/11


user84: Although I tend to agree with the policy you mentioned:

Ask "What does this have to do with Arduino?" and if the answer to
  that question is not significant enough, then the question is probably
  off topic. https://arduino.meta.stackexchange.com/a/52/11

That policy is still quite subjective (how would you quantify "is not significant enough"?) and allows for different interpretations for a given question.
In the specific question aforementioned, I would keep it on-topic for the following reasons:

some answers may be Arduino-specific (or in this case, RFDuino-specific), e.g. there could be some specific way to provide current to the board and keep low-power consumption
the answer may require specific Arduino knowledge, as any datasheet only generally specifies min or max values; but nothing values real-life experience on the board to determine actual power needs
people who can potentially answer this question (i.e. people who already used an RFDuino and have faced the same decision in the past) are more likely to be found on Arduino.SE than EE.SE; as a matter of fact, that's my personal situation, although I do have an account on EE.SE, I almost never go there.


11: <p>Mainly referring to this question: <a href="https://arduino.stackexchange.com/questions/1277/which-voltage-regulator-should-i-use">Which voltage regulator should I use? [on hold]</a></p>

<p>Currently it's put on hold (by me) and has 3 re-open votes from the community so it's obviously worth a discussion to determine what direction the community wants to take this SE in.</p>

<p>The fact that it's an Arduino clone is not relevant to the question. The question is what voltage regulator should I use to get the most out of this battery while still being able to supply X volts and Y current.</p>

<p>When phrased this way, it's obviously off topic. But why does it become on topic if I mention the board I'm trying to power is an Arduino? Take a look at the answers to both Arduino.SE question and the <a href="https://electronics.stackexchange.com/questions/107827/which-voltage-regulator-to-use">EE.SE question</a>. None of them mention Arduino, at all.</p>

<p>We've had a couple of other discussions regarding other topics but they all have the same theme:</p>

<ul>
<li><a href="https://arduino.meta.stackexchange.com/questions/99/are-questions-about-serial-communication-using-third-party-software-on-topic/">Are questions about serial communication using third party software on-topic?</a></li>
<li><a href="https://arduino.meta.stackexchange.com/questions/39/are-questions-about-ides-other-than-the-official-ide-on-topic/">Are questions about IDEs other than the official IDE on-topic?</a></li>
</ul>

<p>My policy is this:</p>

<blockquote>
  <p>Ask "What does this have to do with Arduino?" and if the answer to
  that question is not significant enough, then the question is probably
  off topic. <sub><a href="https://arduino.meta.stackexchange.com/a/52/11">https://arduino.meta.stackexchange.com/a/52/11</a></sub></p>
</blockquote>
 84: <p>Although I tend to agree with the policy you mentioned:</p>

<blockquote>
  <p>Ask "What does this have to do with Arduino?" and if the answer to
  that question is not significant enough, then the question is probably
  off topic. <sub><a href="https://arduino.meta.stackexchange.com/a/52/11">https://arduino.meta.stackexchange.com/a/52/11</a></sub></p>
</blockquote>

<p>That policy is still <strong>quite subjective</strong> (how would you quantify "<strong>is not significant enough</strong>"?) and allows for different interpretations for a given question.</p>

<p>In the specific question aforementioned, I would keep it on-topic for the following reasons:</p>

<ul>
<li>some answers may be Arduino-specific (or in this case, RFDuino-specific), e.g. there could be some specific way to provide current to the board and keep low-power consumption</li>
<li>the answer may require specific Arduino knowledge, as any datasheet only generally specifies min or max values; but nothing values real-life experience on the board to determine actual power needs</li>
<li>people who can potentially answer this question (i.e. people who already used an RFDuino and have faced the same decision in the past) are more likely to be found on Arduino.SE than EE.SE; as a matter of fact, that's my personal situation, although I do have an account on EE.SE, I almost never go there.</li>
</ul>
