But Calrissian doesn't say anything about the Imperials have little close quarters experience. To the best of my recollection, this is the exchange:
Lando: "Yes I said closer! Get as close as you can and engage those Star Destroyers at point-blank range!"
Ackbar: "At that close range we won't last long against those Star Destroyers."
Lando: "We'll last longer than we will against that Death Star, and we might just take a few of them with us!"
No comments on experience there. Lando was picking the lesser of two evils; get in close and get pounded but hope the DSII will limit it's fire while the fleets are merged.
The novel was pretty explicit in that there was little experience with that type of combat, though it also stated that the scale of the vessels was larger here than in previous attempts. Presumably the vessels in the Clone Wars were less advanced or merely less powerful than in the Battle of Endor. It is also likely that many of the vessels at Endor were better optimized for capital ship combat.
ROTJ novelization p.154 wrote:
Desperately, he was shouting into his comlink, over the noise of continuous explosions, talking to Ackbar in the Alliance command ship. "I said closer! Move in as close as you can and engage the Star Destroyers at point-blank range- that way the Death Star won't be able to fire at us without knocking out its own ships!"
"But no one's ever gone nose to nose at that range, between supervessels like their Destroyers and our Cruisers!" Ackbar fumed at the unthinkable- but their options were running out.
"Great!" yelled Lando, skimming over the surface of the Destroyer. "Then we're inventing a new kind of combat!"
"We know nothing about the tactics of such a confrontation!" Ackbar protested.
"We know as much as they do!" Lando hollered. "And they'll think we know more!" Bluffing was always dangerous in the last hand; but sometimes, when all your money was in the pot, it was the only way to win- and Lando never played to lose.
"At that close range, we won't last long against those Star Destroyers." Ackbar was already feeling giddy with resignation.
"We'll last longer than we will against that Death Star, and we might just take a few of them with us!" Lando whooped. With a jolt, one of his forward guns was blown away. He put the Falcon into a controlled spin, and careened around the belly of the Imperial leviathan.
With little else to lose, Ackbar decided to try Calrissian's strategy. In the next minutes, dozens of Rebel Cruisers moved in astronomically close to the Imperial Star Destroyers- and the colossal antagonists began blasting away at each other, like tanks at twenty paces, while hundreds of tiny fighters raced across their surfaces, zipping between laser bolts as they chased around the massive hulls.