David,
As you know, CHEMICAL balancing is between battery cells and the good old hydrometer does this perfectly for wet cell batteries.
The OTHER balancing being talked about above is between individual batteries and, as you know, is necessary (if one is picky enough) so as to keep number of cycles between paralleled batteries identical by keeping amount of charge for each battery and amount of discharge for each battery identical over the life of the paralleled battery bank.
Yes .... it's being picky and not doing it is "probably good enough" .... but why not wire them up in parallel in a balanced manner just because it's not Rocket Science to do it, and it's "the best way"?