I don't use the Cleave option, and the martial PCs IMC have no problem mowing through dozens of mooks. They just have to pay a bit of attention to tactical positioning, so they're not soaking too
vast a number of attacks each round. Recently they've been fighting alongside an army, which definitely helps, but I remember the storming of a castle where the Barbarian had no trouble wading solo through large numbers of guards.
Based on our table's experience, I have to agree with [MENTION=463]S'mon[/MENTION] here, the Cleave option is not a noticeable effect when dealing with mooks, we use it - but it is tactical positioning that plays a much bigger role especially for Battlemasters.
Talk me through this. I don't have my books at my fingertips, so this is just some back of my brain envelope stuff I'm throwing out there.
Let's say 12th level. Orcs are 2 HD (15 HP, 13 AC, +5 hit, d12+3 damage) so at that level they should be in the canon fodder realm. Group of 3 PCs (Champion Fighter, Totem Barbarian and some support class...Cleric or Bard) trying to hold off a horde of them at the city gates (lets say 20 ft "choke point").
Human Champion Fighter:
107ish HPs
GWM and HWM feats (so cleave rider and -3 damage incoming per attack)
Tunnel Stalker for the melee control/OAs
18-19 AC (depending on magic items)
Human Totem Barbarian:
120ish HPs
GWM (so cleave rider and -3 damage incoming per attack) and Sentinel feats
Wolf Totem so allies have ADV on attacks against enemies w/in 5 of you
maybe 15 AC? (depending on magic items)
Obviously Rage, Action Surge, Second Wind, etc. No Cleave and no Mark module. No NPC archers on the ramparts. Just the PCs. Orcs have Aggressive (30 ft move bonus action toward Hostile), so lets assume an encounter distance of 60 ft. Constant steam of orcs. 4 emerging every round from whatever (cave, forest, trench, some obscuring or blocking terrain) and rushing the PCs. Let's call that a wave.
How many (very ballparkish) waves until the PCs falter, do you guys think? Yes I know there are several variables and this can't be answered with absolute precision. Just give me a "I'm a pro D&D vet and x waves sounds in the ballpark" answer.
Melee control, multi-attack/cleave, likely lots of off-turn attacks, -3/halve damage per attack, stout HPs, ADV on most attacks, plenty of single target damage. The major area of danger I see is the Bounded Accuracy one. Even with their respective damage reduction, the PCs will be getting hit a LOT.
Compare that to canon fodder to hit vs AC in AD&D and 3.x. Those ridiculously in favor of the PCs (and 3.x was the most bloody awful iteration of the Fighter there could have been from STs, to default melee control, to the basic action economy working against their fundamental attack mode, etc)
Hit ratio against Defenders in 4e is pretty similar to the hit ratio against a Fighter in 5e. Minion damage to HP ratio is actually pretty similar (vicinity of 10%ish per hit). That is pretty much where the comparison ends.