Some barrels act better with some consistent pressure near the tip of the forend of the stock. Otheres respond well to full length bedding of the barrel channel. The big thing is about making pressure on the barrel consistent, and making the vibrations of the barrel consistent. If a shorter length of the barrel is free to vibrate, then the vibrations may be more consistent.
But if you add in the moisture and temperature effects on a wooden stock then there may be variations in point of impact as seasons change, but still give you some consitency from shot to shot on the day you are shooting.
By free floating, if the barrel responds well to it, you reduce teh effects of the stock on the barrel.
Some barrels may have stressed areas that change tensions within the barrel as it heats up and cools down from shot to shot and won't respond well to free floating,a nd teh pressure pad or barrel channel bedding is still the better route for shot to shot consistency.