I recognise that no one actually assumes that it is impossible for a 5e army to advance in ranks at a steady run.
But I don't really understand where some D&Ders/posters draw these boundaries. Once it's acknowledged that there are cases - and not especially bizarre cases - that the mechanics don't handle well, I'm not sure why there is such frequent hostility to people posting about issues the mechanics have caused in their games.
For me it's really just a question of pet peeves. In this case it comes down to two things:
First, I like things to make sense. Once I notice something, it's hard to un-notice it, and my mind naturally starts working on how to "fix" it. So it's partially from a mechanical sense, that there ought to be a way for it to work better, or more properly. Obviously all of these mechanics are compromises that try to take into account their wonkiness and various shortcomings.
Second, I'm the sort that likes the rules to play a supporting role and not force the fiction to follow or be redefined by the rules. Even worse is when the rules become, well, the rule in the world that produces a different fiction. This is often attributed to the players (metagaming), but to me it's a failure of the rules.
In the current example, we are considering a charge:
The descriptions given before are correct, if the attack comes in the next round, it really is still continuous because the round-by-round construct is simply to help maintain order in the proceedings. Fair enough. Does it make sense?
Well, if a round is 6 seconds, and the charge is actually 10 seconds long, then yes, it should occur in the second round. In which case my mechanics should be different. That is, a charge requires a two-round commitment (as it does RAW now). The only thing that's lacking is the benefit of a charge.
Charge: After a dash (including one in the previous round), you can use an Action to make an charge attack. The other potential risks and benefits (opponent set against the charge, knockdown, tackle, extra damage with a piercing weapon, etc. would still apply.
So this generally turns it into a two-round action, but still grants you the benefits of a charge. It could also serve as a model for other two-round actions. But, this also means that a rogue could use Cunning Action to charge, while a fighter without a feat would take two rounds. This bothers me because I think a trained warrior would be better at it than a rogue, assuming either is. My preference would be that it's the same across the board, and a feat to allow them to be better if they'd like to be.
So the two-round action is OK with me, it's basically saying a charge requires more time to execute than a standard attack (no problem there), but not the alteration in the fiction that now makes the rogues of the world better at a charge than a fighter. One could argue that a defining feature of a rogue is mobility, and fits fairly well with a swashbuckler, and I might agree, but not so much for a thief of assassin.
The prior rule I came up with gives you the attack as a bonus action at the end of the charge. So it does take more time to execute than a standard attack already. It also eliminates the problem with the rogue suddenly being better than a fighter at a charge because of an oddity in the rules. Since we're considering multi-round actions, the rogue could still use their Cunning Action first in the next round, instead of their Action, still giving them an extra edge, just not as great as normal.
With the prior rule you can consider the charge one of two ways: One, it gives you an extra action (or bonus action) because it allows you to take an action and a bonus action. On the other hand, it's recognizing that a charge takes more time than other actions in combat, because it consumes your move, your action, and your bonus action.