It doesn't matter in the least with modern drivetrains in good nick.
Being derived from racing properly set-up indexing will shift under load w/o hurting their feelings, even into some awful cross-chaining.

It's a good idea to have a notion of which chainring will be required to carry a grade but shift when you need to in back, dropping the chain when going for the inner ring at hopeless low RPM is another thing altogether. If you can pick a pedal position to shift from you aren't pedaling fast enough even uphill.

-Bandera