First, let me point out that no donations are needed for this. I'd much rather you understand the system regardless.
I'm not sure what you mean by "strobes", but I will attempt to explain your personal situation in as much detail as possible.
Lets first take a look at a historical graph of your mining hashrate and balance changes:
(...)
I hope this helps you understand the setup better and the details of your particular situation.
Thank you *very much* for this very detailed explanation. Now I'm convinced you are right

Ironically, a couple of hours after your reply, I see some shelved shares taken to estimated during lucky phase i.e. early in the latest round, for the first time in >2 weeks. Looks like I was impatient (and unlucky, as you pointed out) after all indeed.
Donations are never needed but always appreciated, I guess. You can count on the 0.2 BTC donation as promised, I will post txid in a few days, hopefully from my shelved shares

Thanks again for the time taken responding to this, I appreciate it.