Well... I'll be sticking around so can tell you if it helps!
Mind you, I seem to have different types of P so, not sure it will knock them all on the head.
The strep throat definately causes my guttate P... but, I get Plaque P on my elbows and scalp, and inverse P under my boobs (probably doesn't affect you guys).
The inverse P looks shiny and it is totally smooth. The only way I can describe it, is it sometimes looks like a burn. I have the odd sunbed which seems to keep that under control.
Mind you.... funny thing happened about a month or so ago:
I was desperate to cover up the bit of a P I have under my boobs (purely for vantity... you can drawer your own conclusions why).... so I put a little Clinique Foundation on it, then some Clinique Loose Powder (the girls will know what I mean).
Firstly.... it totally covered it up (because the Inverse P is smooth.... there were no bumps). It was completely invisible which was great.
Secondly... and more strangely.... it vanished completely for about 4 or 5 weeks. Of course, when it came back I tried the foundation again and it never cleared it. Not really sure why it did the first time.
But... that may be a tip to anyone who has a patch on Inverse P they want to hide... foundation and then power over the top works wonders to hide it totally!