The purpose of this card is probably to give Brits a TP or FF option, but it does not work out very well. I feel the reason is:
(1) Manor boom is too effective
(2) If I have an additional card to send in age 1 I’d probably go for VC. If I’m already in age 2 I’d rather go for 5 vils or 700w
(3) Quite situational
So the most important is to prevent it from conflicting with manor boom, so that it can become a build order by itself, e.g. one of the following:
(1) TP opening: make the first TP spawn another TP wagon (like Chinese immigrants of US)
(2) Greater effects: also count TCs or markets, etc. for the research time reduction, OR reduce cost as well (maximum effect adjusted accordingly)
(3) Make it an addition to manor boom: TP also spawns villagers when built
The TP built by that wagon should automatically grant 1 transport worth of XP or make natives train faster or something. This way it can compete with the 3 villager shipment.
I haven’t found a time yet when I thought it worked out better than the other options. It is a tempting looking card but has no value whatsoever that I’ve found.
A benefit of it is to age faster. However by using it you forgo eco to age faster and more importantly less eco to potentially pour into survival defense. It conflicts with it’s intended purpose.
As stated it needs a buff of some sort to be viable
I use it sometimes vs civs that are trying to go atp and stagecoach, it doesn’t slow you down that much and you get the time back in the faster age up particularly if you started TP as well.
Is it good for that? You would have to use it as your first card before you could even know if they were going that way. Otherwise if you wait to the second card the tps would usually be taken or at the very least would have to ride down the line looking for an open slot.
The few times I tried it under those circumstances I ended up having to take a native tp as all the spots were either built or started.
In my opinion anytime you send GWT it should be your first card in lieu of 3 vils. Generally you will follow that up with Virginia Company to make up for the lost vils, as the extra XP makes it come in earlier. GWT is still situational either on ATP maps as Knot said, like when you know Port is going ATP before even looking at deck. Just eating up a couple TP slots is useful in those situations, but then I would also recommend just going heavy on musk after GWT rather than trying to do an FF. You get to send all of the musk combat cards much quicker.
And while grenadiers aren’t usually viable, if you want to try them, GWT is the way to go for all of the musk/gren cards.