The question should be "Should Scotland leave the United Kingdom and become an independent sovereign state?". Very simple and candid.
Devo max has rightfully been rejected by Cameron because it's a silly idea. It would bring all the negatives of a federal system (inconsistent business laws, tax loopholes, more bureaucracies etc) but due to it's lopsided implementation in the UK it would bring virtually none of the benefits.
It would be like if America actually only had 2 states. One being California and the other being a flyover state like Minnesota. England would have to divide into smaller states too to make it relevent, but it seems the UK is too small for a federation.
In fact we should never have given them a Parliament in the first place - it's already proving detrimental to the UK overall - but the genie is now out of the lamp and it won't be revoked without a hissy fit.
If Scotland wants Devo Max they can go it alone, but they can't hold the rest of the UK to ransom to get their own way all the time. It's either in as an equal or out.
Salmond is of course fishing for a reaction like this off Cameron and the population of the UK because that is his plan: create a divide and animosity that doesn't exist between English and Scottish people. If they keep arguing long enough they'll hate each other and both will want to go their own way. This is probably why we have to wait so long for an answer to the most basic of questions. Sigh...