The Hitch said:
I would rather people just call him NImek or something, than try to pronounce it the way you have laid out.
You are mostly right of course but Polish requires a lot of tongue work that takes years to perfect and that non slavs are unlikely to ever grasp. Hell i have heard lots of people who began learning Polish in their 20's or 30's whose grammar is good, but it takes a lot of work to actually be able to understand what they are saying.
Some people even require operations on their tongues to be able to speak proper Polish.
The "s" or "sh" like sound after the p involves curling the tongue up into a "c" shape and having the bottom touch the roof of the mouth. The sound produced kind of resembles the sound of a waterfall.
The cz sound like in Rutkiewicz requires a similar commitment from the tongue but the c sound this time.
And the rz sound involves yet again the "c" shape only a z sound.
I hope the commentators just call him Nimek.
Call Sil-ves-ter- "Shmid" call Marek "Rut kiawik" Call " Yaroswaw -"Marik" and so on.
It would sound a lot better than attempts by even the most skilled linguist to produce sounds that their tongues just arent used to.
Its nice to hear different variations of the names once in a while.
I know (or rather, am aware of - cannot tell the difference in speech because my Polish never progressed beyond basic) the differences (sz, cz, rz, ż being retroflex while ś, ć, ź are palatal) but:
1) as you say, it's hard to actually learn unless you've grown up with a Slavic language or at least a language which differentiates retroflex consonants (eg Arabic) - I am absolutely useless at it; I can produce the sound more or less correctly in isolation, but ask me to put it in a word or sentence and I screw it up every time
2) Linguists tend to transliterate the retroflex consonants with ʃ and ʒ like they would their non-retroflex counterparts for ease of transliteration
I know a lot of people have trouble with non-native sounds, what I put in above is a simplified version of how to best approximate the original; I felt like I'd gone too far into linguistic jargon already before putting in statements like "retroflex interdental fricative"

. When I was learning Arabic, the biggest problem I had by far was learning to produce ayin; it's a complex procedure to teach yourself new sounds like that.
The other thing, of course, is that 'Szmyd' is just a rendering into Polish of the German 'Schmidt', so it's not surprising that people would automatically just read it like the German. And with most of the Poles I knew we always communicated in German, so it's very likely that what I do know is contaminated by the use of German amongst us as a lingua franca, so I've probably underestimated the level of differentiation between the sounds in spoken Polish.
There's a fine balance. If you try to speak every name as it would be in its native language you're going to wind up marblemouthed as you switch from linguistic mode to another, and confuse the audiences (especially as you come across more and more sounds that you aren't familiar with unless you're a true polyglot). On the other hand, just reading out the names any way you like is disrespectful (and also we get a lot of inconsistencies, which also creates confusion, with the same names said 5 or 10 different ways).