Obviously it's always better to do it all in one sitting, however, what are the effects of

weekend 1

wash/clay/remove medium swirls


...drive around highway, town, etc..



weekend 2

wash/polish/final coat

Let's assume that there's no way of doing it all in one weekend for argument's sake

 

I wouldn't polish or wax without having washed/clayed immediately before polishing/waxing.
What I'd do is do the wash/clay/polish/wax the doors and probably front/rear qtr panels one weekend, then wash/clay/polish/wax the hood, roof and trunk the next. That way you're doing all steps one after the other on a single section.

 

Agreed. Do what you can finish (wash/clay/polish/protect)...You never know what circumstances my arise between now and the next opportunity.
Maybe do all horizontals, or verticals one weekend, then finish up next opportunity.