meta: separate or combined postings for loosely related subjects?

(no British English spelling checker active - yet) On one Q&A platform 
one question sparked my interest in coding multiplication for AVR, and 
some of the results (especially retiring two multiplier bits instead of 
one at very little additional cost) have looked like GCC for AVR should 
profit from it(in part for Atmel Studio still including a libgcc 
predating gjl's 2012/08/24 
rewrites)(<http://stackoverflow.com/questions/29812009/faster-16bit-multiplication-algorithm-for-8-bit-mcu>).
With my mind still not made up about how to contribute (dumping it to 
bug tracking being the timid&lazy option), let me start with a meta² 
question: Do you prefer each of a few subjectsbrought up by the same 
occasion(like discriminate "optimise time" by expected vs. worst case; 
implementation of symmetrical operation with decided asymmetry in cycle 
count between operands; code generation for multiplication by constants 
for 2 vs. 3 address architectures (and weird intermediates like the 
AVRs); choosing between not totally ordered implementations, testing 
multiplication; avr.md vs. -fixed; multilibs) in a separate posting, or 
should they be kept together, if at the risks of postings as long-winded 
as this question?

regards,

HoW

-- 
Wolfgang Hospital