After a test run on the Southern California Traction Clubs city modules, the drawbacks of single truck trolleys became apparent on ol' 301.
Sir Lord Dr. Isaac Nudeton Esq III PHD.
Nudeton's 3rd law of force states: "The force of the trolley pole pressing up against the overhead contact wire is equal and opposite to the force pressing down on the trolley car.". Who knew Nudeton was a trolley fan!
Well that force was evident on the Birney car. The pole pressing down on the back of the car coupled with the fact that there is a weight behind the decoder puts more force on the back wheels than the front wheels. So the back wheels become in effect, a fulcrum. In other words, the trolley wants to do a wheely.
And a trolley that wants to do a wheely doesn't want to take curves, it wants to keep going straight.
So the solution is: More weight in the front of the model, get those front wheels down so that the flanges will help the trolley get around corners.
So after making the bold statement of "There is officially no more room for anything else in this model!", I have to find more room for more weight in the front of the model. Yes sir! Have to find more room!