Yes I've seen that as I've checked for fake shares when I noticed your 'experiments'.
Well.. Yesterday someone on slack told me that a gpu miner would be technically impossible

Show it or it doesn't happen. Simple.
not sure how much interest this will get but here goes.
have been playing with the original cpuminer since zcoin's release; and seem to have found a slight edge last night.
performance gains are in the realm of about 25-50%, earning about 0.5 XZC from one quad cpu VPS overnight (9-10hr).
please note that the reported hash below is wildly incorrect, it should be around 20H/s or slightly higher from a standard 10H/s.

as some of you know, i'd been toying with a GPU miner since launch as well; with some partial luck; probably more to ocminer's annoyance with the invalid shares he keeps seeing on his pool from me

going to give it another go night and will report how i go.
baz
(the black spaces are just some debug information ive removed)
Okay 25-50% increase on performance is possible since I had a small tweak in the memory controller and got a 20-30% boost as well.
wolf0 has a similar tweak and he already showed the proof so I believe that your statement about the performance increase is possible. You might overestimate it a little bit since the algo is a bit crazy so the miner gave the wrong hashrate sometimes too.
Enjoy it for a while (well I honestly think all the big miners already have it as well), since we will switch the algo soon.