These two shortcodes [bwtron] and [bwtroff], from the oik-bwtrace plugin, may be used to turn tracing on and off during the “execution” of a page, post or widget.
Whether or not you get any output traced between the calls depends on the code being invoked. If there are no calls to the functions bw_trace(), or bw_trace2() or bw_backtrace() then there won’t be much output.
Here we are going to trace the execution of the [bw_plug] shortcode.
[bwtron] oik [bwtroff]