If I may chip in supporting examples from Karnataka: what I have seen routinely in Sanskrit manuscripts there is the assimilation of the visarga and the following sibilant: nissaṃdehataḥ, niśśabdatvam, etc. etc. Therefore a word like nissaṃdehataḥ, which is also used in a more highly literary style of Kannada, is written just so: ನಿಸ್ಸಂದೇಹತಃ, and in libraries one can see signs that read ನಿಶ್ಶಬದವಾಗಿರಿ – niśśabdavāgiri 'be quiet'.

Robert Zydenbos

Dominik Wujastyk via INDOLOGY wrote on 09.08.22 21:31:
"overwhelmingly" only if you judge mainly by print sources.  In my experience, manuscript scribes from Nepal and from Kashmir routinely use sibilant-assimilation sandhis of the form namaśsivāya.   […]


On Thu, 4 Aug 2022 at 18:28, Harry Spier via INDOLOGY <indology@list.indology.info> wrote:
[...]
1) 
namaḥ śivāya is overwhelmingly written namaḥ śivāya and rarely as namaś śivāya or  namaśśivāya .


--
Prof. Dr. Robert J. Zydenbos / ಪ್ರೊ. ಡಾ. ರೊಬೆರ್ತ್ ಜೆಯ್ದೆನ್ಬೊಸ್
Institute of Indology and Tibetology
Department of Asian Studies
Ludwig-Maximilians-Universität München (University of Munich – LMU)
Germany