rspec users - Nov 2007 - spec.opts default --load-by and observers

When specing observers I usually put them into models directory under / 
spec. Then, when specs are run observer class can''t be found unless I  
remove --load-by mtime from spec.opts.

My question is what''s the Big Idea behind loading specs in that order  
by default? Shouldn''t default spec.opts contain just formatting  
options? Because as you see it DOES cause problems and though it''s ok  
for me, some RSpec users may be pissed off after first trial of  
testing observers with RSpec.

WDYT, David, Aslak, others?

MK