Throughout my history of playing the classic scenario I have come across different city leveling techniques, and despite not truly testing them all, I am curious to see the reasoning behind them since I have been loyal to one style which I believe it's most efficient, and I will explain why. Now, the game has evolved, and players have found and developed strategies to accomodate pretty much everything, from gaining prestige, farming money and efficiently leveling the cities, to
finishing the end game in record time. Therefore this is not about hammering the RGs until the city levels anymore, of course, but like I said, some techniques still persist.
But first, let's create some context, and for this I can think of 3 test cases:
1. A city with one big association.
2. A city with two big associations.
3. A city with 4 associations, medium to big size.
It's important to think in such terms because not only the association friendly statuses matter, or matter less, but some leveling techniques can benefit more from a given format.
A. The first strategy pretty much implies no strategy, or let's say lesser strategy, named here strategy A. At some point, somebody will say "let's level-up the city" and ask everybody to switch to direct hauling the RGs. Now, and this is interesting, if there is only one association, I have seen the caller to ask everybody to haul ALL the RGs, not only one. Of course, when there's only one association it really doesn't matter much since it will hold majority in all industries, but still, very odd and like I said, very little strategy here. I for one think this is the worst style since even if there is only one association, you can still do things a bit better. Why I think this is the worst? Since the industries will quickly burn out and have high wait times, especially the low level industries, since leveling the city will probably take more than one hour.
B1. A somehow better style than strategy A, called strategy B1, one that also doesn't imply much, is the offline hauling level-up. Well not exactly completely offline, but the catch is to hammer the RGs regardless of how they are hauled (I would assume is mixed, some do integrated, some direct, some a mix of both) and wait for the city to tilt. If somehow one RG is trailling behind, of course it gets helped, declared or not declared. I have seen this so called strategy even on large groups of 4 associations, which for me is baffling since things can be performed so much better. My strongest objection towards this strategy is that, until someone switched their trains or a caller asks this on the city forum, some RGs (maybe even 3) can be hauled in yellow or even green territory for hours, generating abysmal profit for a good majority of players.
B2. A rather very similar approach to B1, named simply strategy B2, is also an offline hauling level-up technique but when a caller asks for one-step integrated train schedules. For those that don't know what one-step integrated is, sometimes called one-stop or short chain, is when for example a city requires Leather as an RG and the player only hauls Cattle to Leather to City, skipping on Grain. This type of hauling will put pressure on the Cattle site but won't strain too much the Leather one since it will have it's supply delivered (i.e. Cattle). This comes particularly in handy when an RG has a long chain of supplies or they are very far apart. If all my knowledge would stop here I would consider this to be the best approach so far when leveling a city.
C. Strategy C is what I commonly use and I have found it's widely accepted, and it implies a mix of proper hauling and proper calling. I usually let people know in advance that we intend to level the city starting with a certain hour, and I ask everybody, before signing off, to leave their trains running their assigned RGs integrated, preferably fully integrated. If I notice that one or more RGs are trailling behind, I ask on the forum for players (preferably those that belong to an association benefiting from a friendly status) to switch some trains so that the trends grow as equally as possible.
At some point, usually when the stocks are getting filled more than half (or the city gets filled up to almost 70%), I would ask for the players to switch to one-step integrated only, to further speed up the process. After a while, if the stocks are hitting almost yellow (or the city gets filled up to almost 90%), I will ask everybody online to switch their trains to direct haul starting with the next recalculation (to avoid industry level-ups under one hour). In general we level the city within one hour, one hour and 15 minutes, from the time the call for push was made, during which time I always make balancing/adjusting calls to equalize the trends.
So you can see, my approach is progressive and I make sure to take advantage of both offline and online hauling power correctly. I believe this is very efficient and leveling a city usually takes under 3 hours, once I decide to adjust things around. I have used this method when having 2, 3 or 4 associations, but is significantly stronger, and beneficial, when having 4 associations since the chance of them to be equal in strength is slim (albeit not having equal number of members, equal number of online players and, in general, equal game knowledge).
The main drawback is that it requires an active caller and a handful of responsive players around for this to work, otherwise switching to direct haul and missing one recalculation to level up can have bad side effects (very high wait time or industries leveling up and having their investments reset).
D. And finally, at least for my knowledge, strategy D, also known as the 2x2 (two by two, refering to RGs). This is something that I don't see very often, but have tried it nevertheless, and found it to be lackluster or extremely niche. It's basically strategy A but with a twist, where players direct haul ONLY two RGs for one hour, before switching to the other two, after recalculation of course. Why I consider it to be extremelly niche? Because it's best suited for cities with one or two big associations that have pretty much the same timezone, hence they can be online preferably during the same time. And why I consider it to be lackluster? Because you're never going to have MORE online players than offline, it's just how things are, and leveling a city may take up to 3-4 hours of constantly switching. I would very much be patient and wait for the stocks to steadily grow up to 90% before going for the push. This way I don't involve ALL the online players too much, leaving them more free time on their hands and only ask for their assistance when pushing the city which, as I've said, should take one hour, give or take.
I am curious to see if there are other strategies that I don't know of, for the classic scenario, and what's your take on the four strategies I've detailed above. Maybe you also have developed your own style, mixed or some sort.