Well it's nice to hear from some folks on this site who actually fish on an actual river.(not internet fishing,as some here seem to be doing..
...and a couple of others...you can tell these guys fish,by what they say,real world techniques that work in real fishing situations.
The Perry Polk is a very useful cast-tool to have,and when done correctly is an aesthetically nice looking cast(not that that really matters)....A person can fire out a whole hell of a lot of string in a lazer tight loop with this cast.
I use the Perry Polk as a stand alone cast,when the situation calls for it...when the situation calls for a; single,circle,snap or double,I'll use one of those...it's called being versatile in your "FISHING" casts.
If your casting little pieces of yarn at a clave,that's one thing.
Casting real flies with weight or not and possibly tips, in high wind standing in waist deep,and deeper water, with the overhanging bank scratching your back,and doing a precarious balancing act on slippery rocks...well you learn to be creative with your casts,and that makes you a better caster,and more effective fisherman.
Nothing beats being out there every other day or so and casting in these real world situations.