Train in your way on KD? Here's what you should do with your mushrooms.

0-1-2 Newbie F - 1'51"50
If you're very new and don't have MTs down yet, start off with 0-2-1 until you reach the 1'52 range.
- Shroom once through sand after 2nd train crossing on lap 2.
- Double shroom through sand after 2nd train crossing on lap 3.
If you're around 1'57 pace, the 2nd train on lap 2 will be in your way with this strat. Go behind it or keep grinding until you can make it in front of that train.
You'll know it's time to move on to the next strat when the first train on lap 2 is unavoidably in your way.

3-0-0 1'52"00 - 1'46"50
Now that the first train on lap 2 is in your way without using shrooms, it's time to make sure you can go in front of it. Use all 3 shrooms on lap 1 to do this.
- Shroom once over the sand hills at the start.
- Double shroom through sand after 2nd train crossing.
The 2nd train on lap 3 will cause problems on this pace. Unfortunately, at this point it is probably better to just go play other tracks and improve your driving so that you can make it in front of this train.
You can slow down and go behind it while still in the 1'50s. Once your driving is good enough, you'll be able to make it in front of that train and get 1'49s and lower.
While you can continue to use this strat into the 1'46 range, it's going to be better to move on once you get into the 1'48s

2-1-0 1'49"00 - 1'46"30
Once you're beating the first train on lap 2 by a good margin with 3 shrooms, you can move on to trying to make it in front with only 2 shrooms.
- Either double shroom through sand after 2nd train crossing or 1 shroom at the start and one at the end.
- Shroom through the sand after the 2nd train crossing on lap 2.
Once you've gotten down to a mid 1'46, the first train on lap 3 will be in your way. Time to move on.

2-0-1 1'47"00 - 1'45"60
We can avoid the first train on lap 3 by saving a mushroom for the end of lap 3 instead of using it on lap 2.
- Either double shroom through sand after 2nd train crossing or 1 shroom at the start and one at the end (double shroom is a little slower).
- Shroom through the sand after the 2nd train crossing on lap 3.

1-1-1 1'46"30 - 1'45"20
If you're looking for something just a little faster now, 1-1-1 will get you there. You'll have to be able to beat the lap 2 train with a single shroom though.
- Shroom in the sand after the 2nd train crossing on each lap.
This is the best way to use your shrooms, but now the first train on lap 3 might be in your way again.

1-0-2 1'46"20 - 1'44"00
Since we're driving too fast and that lap 3 train is in the way, save an extra shroom for the end. Hopefully you're doing hill hops at this point too.
- Shroom in the sand after the 2nd train crossing on lap 1.
- Double shroom after 2nd train crossing on lap 3.
If you're reaching low 1'44s with this, then you're going to be cutting it close to the first train on lap 3. Time for the train gap.

1-1-1 1'43 and beyond
No avoiding the train here. WR drives between the train cars on lap 3 and shrooms once each lap.