No, Luther did not "kick start" the Reformation over a few pints in a tavern. If you can pick a moment, it's probably the Leipzig Disputation of 1519. The 1517 Ninety-Five Theses and public reaction absolutely launched a reform movement. But if you want to point to The Reformation as an actual break in the Church, you have to look at Leipzig. Although Luther mostly wiped the floor with Johann Eck, his opponent, Eck walked Luther into declaring that the pope had no real power and Church councils could err, in other words, heresy. The papacy recognizes this a few months later with Exsurge Domine, the papal bull excommunicating him.

However, Luther does use beer as an important literary device in the first Invocavit Sermon, which might be what the book is referring to. Notably, this series of sermons occurs when the Luther movement (Reformation) is well underway, and in fact, they are directed against Reformers who Luther thought were taking things too far.

Take myself as an example. I opposed indulgences and all the papists, but never with force. I simply taught, preached, and wrote God’s Word; otherwise I did nothing. And while I slept, or drank Wittenberg beer with my friends Philip and Amsdorf, the Word so greatly weakened the papacy that no prince or emperor ever inflicted such losses upon it.

But you can see that "drinking beer" is a literary device here (although presumably he had drunk quite a bit during the time frame in question). It's Luther's way of asserting that God's Word (Jesus/Scripture) do everything. Humans have no power (...and consequently Wittenbergers need to ignore Karlstadt and the other proto-radicals).

Well, Luther for one was certainly known to enjoy his beer, but to my knowledge there's no record of him frequenting pubs or taverns and such visits influencing the course of the Reformation. Probably what that author is referring to is his Tischreden or "table talks", which are an important source for Luther's thought. Luther's house was known for always being open to guests, most especially young students at the university; in fact, his and Katie's house was sometimes more like an unofficial dormitory. After dinner, Luther was known for going into his favorite room, a sort of a parlor, to kick back and enjoy some good beverages and stimulating conversation with his guests. A number of students who were at these gatherings later took notes of things Luther said and collected these into several volumes of Tischreden.

He was fairly forthright about his love of beer in his letters too, for example:

In short, I will preach it [the Word], teach it, write it, but I will constrain no man by force, for faith must come freely without compulsion. Take myself as an example. I opposed indulgences and all the papists, but never with force. I simply taught, preached, and wrote God's Word; otherwise I did nothing. And while I slept, or drank Wittenberg beer with my friends Philip and Amsdorf, the Word so greatly weakened the papacy that no prince or emperor ever inflicted such losses upon it. I did nothing; the Word did everything.

Of course, cultural norms for alcohol consumption were different from today, and especially different from modern America. In one of his table talks, Luther mentioned that he didn't think children under the age of 8 should be given wine to drink. So sitting around informally discussing things over beer might not be quite as analogous with a modern bar or pub. Of course, alcohol does have the effect of lower one's inhibitions, so a psychyanalytic approach to history could speculate what difference that may have made; in fact, I recall reading a book a while back (History of the World in Six Glasses, I think it was called) that made an argument about the shift from alcoholic beverages in the Middle Ages to non-alcoholic drinks like coffee and tea in the Enlightenment affecting the intellectual direction of culture.

So I think it is fair to say: as Luther discussed theological matters, refined his thoughts, and shared them with his fellow Reformers like Melanchthon and Nicholas von Amsdorf as well as his students, a great many of those discussions may have happened over a few beers or glasses of wine. However, I don't know of any German analogue to something like the White Horse Inn where a group of nascent Reformers did gather in a public tavern for their discussions.

Edit: Here are pictures from the "table talks" room in the Lutherhaus in Wittenberg, including a picture of one of Luther's own drinking mugs.

Pubs, I'm not so sure about. Luther did seem to spend a good deal of time drinking, but most of Luther's beer came from his wife Katie. The Black Cloister where they lived wasn't just their house, but an inn for local students, visitors and more. Katie did not only manage the household, but also the inn where Luther would do most of his drinking. On top of that she was its brewmaster, and a very good one. In fact, the Wittenberg Party at the Diet of Augsburg insisted on bringing barrels of Katie's beer from Wittenberg to Augsburg - whether that was because Katie's beer was really good or because Augsburg beer was notably bad is less determinable.

Source: Timothy Lull, My Conversations with Martin Luther