Matt Whiting wrote
That's one reason I wrote earlier that I'll be curious to see if Mike R.
changes his opinion one that he's beginning his ATP.

I'm betting that if he trains with a real, practicing ATP (meaning
someone who flies in a crew environment day in and day out) he will.
If not, not.

I don't care whether in sports, shooting, flying, motorcycling,
etc., I've always used the "train as you X, X as you train"

Well, that's your choice - but I believe in cross-training. There is
value to getting out of your comfort zone and doing something
different from, but related to what you do normally. I believe in
tailwheel training for trigear pilots, glider training for power
pilots, rotorcraft training for fixed wing pilots - you name it. Not
at the initial stages, but once you reach a level of proficiency where
there are only very small gains to be made with further practice,
cross training opens up new perspectives.

The essential point is that at some level, the best bet in improving
your skills at X is to do Y. If I'm doing a recurrent training
session for a multiengine pilot and he executes a near-perfect single
engine partial panel non-precision circling approach to a short
runway, I will not suggest to him that he should keep practicing this
until it is absolutely flawless. I will suggest that he get into a
glider, or a seaplane, or a biplane - something different.

If you don't believe in cross-training, you're not going to suggest
that.

Michael