Regression with soft sounds

Question

How strange would it sound to make the preceding consonants soft in the following words?—

All examples are from Jones and Ward (1969) The Phonetics of Russian. Furthermore, all examples are from the speech of the older generation. In other words people did speak like this at one time (or still do)--

(I mean the С)

спичка, смена, сфера, свет, смех

(I mean the м)

лампе, бомбе

(I mean the в)

деревня, дешевле

My question is— how strange (bad) will it sound if I make letters soft that should not be soft, or letters that were soft in past generations, but are not now?

Is it not such a big deal to make some mistakes in softness?

Answer 1

Actually i believe i've heard some people a feature of whose manner of speech was a degree of softening of the C's and the M's before soft consonants like in your examples. Not sure about B though as it seems to me quite resistant to softening in blends with soft consonants, i've tried it and it's not easy or convenient.

What i heard sounded a bit odd to me, rather funny, but acceptable. Can't speak of other cases, i'd need to hear them to make any judgement, but palatalization has potential to severely distort the way the language sounds, so its acceptability depends on the degree of resulted distortion.

At the same time accent is not that much of a problem, but from social perspective in order to be acceptable it at least has to be referential to foreign or regional background. An accent must be natural and not arbitrary, whimsical or one-off.

Answer 2

It would sound archaic or regional indeed.
My grandfather, for example, keeps softening the с in words like свет, последний, косвенно. However he is both elderly (turning 88 this year) and he was born in a village in Tambov region and moved to Moscow at the age of 14, so his speech has some interesting dialectal features, besides that regressive assimilation. He is not the only (aged) person I heard this softening from.
This softening is part of a larger feature set called the old Moscow pronunciation. There palatalization went even further: четверг is pronounced like "четьверьг", церковь — like "церьковь" and so on. This is another thing, but nowadays also quite rare. If your Russian is good enough, I highly recommend to read this Wikipedia article, especially the section about the old Moscow pronunciation (Старомосковское произношение). The corresponding article in English is quite poor so far, unfortunately.