This basically eliminates the upperhand of objective-based games. Normally, when a team is holding an oddball or a flag, it's 3 defenders & 1 holder versus 4 attackers; this gives the attacking team a better chance at attaining the objective due to more firepower.
Assuming two teams are equal strength and skill, it would almost come down to who grabs the objective first to determine who wins.
I mean, don't get me wrong, I would love to assassinate an enemy with the flag then turn a magnum 4-shot double kill, but it definitely will change the pace and flow of gameplay having even firepower.