can someone advise?

In the PLANT FILES section of this website, under Dahlia cultivar 'Harlequin' it says the propagation method (quoted) is:
Propagation Methods:
By dividing rhizomes, tubers, corms or bulbs (including offsets)
From herbaceous stem cuttings
From seed; sow indoors before last frost
From seed; direct sow after last frost

But then immediately says under seed collecting (quoted):

Seed Collecting: N/A: plant does not set seed, flowers are sterile, or plants will not come true from seed

I don't understand this - seems like a contradiction.

Also, does anyone know of anoher name for a cultivar not listed here called "Hello Gorgeous"?

Uhmm...I'm not 100% sure. But I do know that we, the people (smirk) can enter the plant files ourselves, and make mistakes. When you're entering it-it asks you all those questions listed under each var. info and I wonder if some of the little things either get skipped or just not answered. I know I've entered one and just halphazardly breezed through some of that part. I'm sure that variety probably does put out seed, if you know how to collect them. Maybe someone just biffed on that part?
As far as finding, or not, certain varieties-that's because no one has entered it yet. I've not found a lot of varieties before. So, if you have info on it and a photo (not necessary), you could enter that one.

At least, that's how I think it is. Hopefully I didn't completely steer you in the wrong direction. lol

Re: Hello Gorgeous - http://davesgarden.com/community/forums/p.php?pid=7738702

It's not the name of a cultivar but a series of dahlias.

Re: confusing information on Plant Files

IF a dahlia provides fertile seeds you'd follow that information but in the case you present the flowers are sterile so there would be no point in trying to grow sterile seeds (provided that statement is true).

Not everything is 100% perfect on PF. Treat it as a good guide.

Thanls for the helpful info... also good to know that PF is not always accurate - I've always thought of it as an area of authority.

The plant heights drive me to distraction when they say "24 to 36"". I need more specific information when planting a garden. Colors can also be very confusing but I do rely on the PF photos.

Thank you! I totally agree on the heights! They need a more specific range. Big difference in where I'll put it or if I'll even get it if it's 4' or 6'!

It would help if, as we enter our photos, we could say how tall it grows for us.

pirl's last comment would be the most helpful. How tall the dahlias grow in each individual garden will vary big time.

It will vary but at least we'd know if 3' was more common than 5' and that alone would help with placement.

I think what they mean is that if you harvest seeds from the plants they don't really qualify as the true "Hello Gorgeous" type. I could be wrong though. I collected seeds from the plants last year and tried out a few and none of them produced a seedling. I may try some more here in a few weeks.

I found a dried up seed head and "just for fun" scattered the seed in my tomato box: I've got dahlias! No idea of the size/color/height/form but it will be fun growing them.