Joe --
It's a comparison I've often made myself in terms of relative value and utility, so I can't agree. Personally I feel that Doyle's argument makes good sense.
I'll go one further. Let's say that Al Gore was elected President instead of George W. Bush. And let's say that President Gore believed that operation of traditional gasoline combustion vehicle was a moral wrong, a great evil perpetuated on the environment. So one day he went on national tevelvision to declare that after January 1st of the coming year, operation of all such vehicles in certain states would be illegal.
President Gore might even would cite Abraham Lincoln's Emancipation Proclamation as a precident.
But to return to the topic in question, none of this was being discussed in 1860. What was being discussed was the victory of the Black Republicans and what it would mean to the South. You have only to read any Southern (or Northern newspaper of that time) to get a good sense of the slavery argument on the day. Many Southerners had refused to support Douglas in the election beause he wasn't trustworthy on the slavery question. Southerners then moved towards secession as a solution to the Black Republican problem.
This doesn't invalidate most of Doyle's points, but I prefer to face the slavery question directly, just as most people in the South did in 1860.