Are repeated crossing and uncrossing of hands the "correct technique"?

[1piano4joe]

For Example.

Left hand plays. Right Hand plays. Left hand crosses over right hand to play.

Now the same RH/ LH figure appears exactly one octave higher. Remember my hands are crossed.

Must I uncross my hands?

First, I uncrossed by keeping my left hand stationary and moved only the right hand from under the left one to an octave higher to the right then leaving the right hand in place I recrossed over the right with the left. No problem by the way.

Second, I tried leaving my hands crossed with left over right and moved them both simultaneously one octave higher to the right. I had never done this before and it seems just as easy maybe ever easier. I found that letting the top left hand lightly touch the right hand underneath helped preserve the hand positions during the shift and made it simpler still.

Is this an accepted alternate technique that is at the player's discretion or must I cross then uncross then cross then uncross?

Also, just curious but is it okay to cross hands ahead of time? In other words, does anyone cross the left over the right as preparation? If the left hand is not playing because of a rest then why shouldn't I move it ahead of time while the right hand is playing? Usually, I play the right and then have to cross the left over and shift to a new position in a rushed fashion.

Similarly, can I uncross ahead of time?

This seems (to me anyway) like page turning where I just do what's most convenient. Is that how I should look at it?

This is from a piece called Scaly Things By Stephen Chatman in RCM piano etudes Level 1 which is a cross hands study.

Interestingly, the penultimate measure has an 8va which I believe applies to both staffs. Is this correct? The eighth note in the bottom treble staff is beamed to an eighth note in the upper treble staff. If I am correct in assuming that the 8va applies to both staffs then is it because of the beaming or because both both top and bottom staffs are G clef? Lastly, if I were wrong then why does the word "loco" appear in the last measure of the left hand which is now in F clef?

Any tips, insight or corrections as always are greatly appreciated. Thank you, Joe.