*don't* fail when bck-i-search is over

[darwin <darwinskernel@gmail.com>]

hello,

i've this in .zshrc

zle-line-init(){
	zle history-incremental-search-backward }
	#zle -K vicmd;}
zle -N zle-line-init
bindkey -M isearch "^I" vi-repeat-search
# bindkey -M isearch "^I" history-incremental-search-forward

1. it _almost_ does what i want it to do which is to start off on bck-i-search. the idea is that with cli as the main interface, user have issued his most commonly used commands already and so it makes more sense to look into .histfile (or whereever) first. as a result the system is now screaming. well, it's all great util user wants to issue a never-issued-before command. one way to do this is to get out of bck-i-search and do it there (viins, vicmd, what have you). but a more elegent solution, i think, is to have shell start digging the $PATH for possible completions once it's done with the .histfile. that way performance wouldn't be comprimised and user is still doing the same thing (keep begging the tab) to get to where he wants to go. is there a way to do that? 

2. the commented lines are what i had before. with all my _elegant_ solutions there are still situations when i would still want to edit a command and that's when i would prefer to go back to vicmd (it's a matter of muscle mm really). but with my current setting:
	bindkey -M isearch '^[' send-break
hitting esc gets me out of bck-i-search and dumps me into emacs! i even tried with
	bindkey -v
but that's half-baked because i esc bck-i-search into viins and not vicmd. i would appreciate any help with this one also and thanks in advance.