This is simply not true. Read the accounts of the officers actually at the battles. Probably the most used phrase is "they fired a volley and then charged with the bayonet". Often times regiments will simply charge and not even bother to fire a volley.Bayonet charges into enemy ranks were not common and they were done only when the other side was starting to show signs of breaking up.
Even if this was true, it would merely confirm my statement that the musketry fire was aimed at disrupting the opponent and the bayonet charge was used to force the issue and finish them off/drive them from the field.
If musketry was 'better' than bayonet charges, you wouldn't bayonet charge when your opponent was starting to show signs of breaking, you'd keep doing your musketry thing as there'd be no point to switching to a less lethal and less effective form of combat.
Charges to melee by infantry were extremely common and arguably the *most common* form of attack to seize ground. The idea that they were never used is rather implausible, especially considering that dozens of such charges might be launched back and forth to secure key areas like villages.
There *were* extended firefights (read, lasting about 10 minutes in the extreme cases) but these were far from the norm and usually occurred when the attackers had already lost a bit of their nerve and decided to engage the enemy in a shootout rather than pressing their bayonet charge. Theses cases usually resulted in a repulse for the attacker.
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