Freehling on Secession?

Michael Holt has argued that the lower south promptly seceded after Lincoln's election while the middle and upper south did not because, among other things, the lower south had never developed a viable two-party system. Cotton south Democrats thus lacked the experience of falling out of power and then rallying and coming back in the next election. When Lincoln won in 1860, they did not see it as a potentially temporary setback, to be overcome by normal democratic processes, but rather the beginning of permanent minority.

One thing for which I've been on the lookout for, while reading The Road to Disunion II, is whether Professor Freehling agrees with Holt's theory, in whole or in part. Here's the first suggestion of a positive answer I've encountered (at 96):

Thus where the heavily enslaved Lower South's experience with nativism [the American Party in 1854-56] had yielded a largely one-party system, with the hapless ex-Whig remnant in position only to carp at the proslavery Democracy, the lightly-enslaved Border South had regenerated a competitive two-party system, with the powerful ex-Whig fragment in position to defeat the Democracy. The Lower South and Border South had generated different political institutions, compounding their different social institutions. In 1860, the borderland's powerful surviving ex-Whig partisan organizations would give the region's Unionist Party a leg up in defeating secessionists. But in the Lower South, the uncompetitive ex-Whigs would offer no such institutional bulwark against disunion.