It doesn't make a sweeping statement of all the Romance and Germanic languages, a position I may have mistakenly represented in my last post. The argument is in the opening article of "Moods in the Languages of Europe" edited by Björn Rothstein and Rolf Thieroff. You can find a Google preview here, but it's unfortunately missing some pages. It basically boils down to analysis of tense vs. mood, placing conditional as a tense (past future, basically). It is suggested that imperative could be analysed as a sentence type akin to declaratives and interrogatives. I misremembered; it only lists Germanic languages as being in the process losing subjunctive and thus becoming technically moodless. As always in the field, it's mostly a matter of definitions though.