If you use the NI proposed way of creating Sub-VIs for functions (which is good), debugging soon becomes a nightmare with every VI opening two windows, one of which is mostly not needed (the front panel). It would be great if LV gave us an option saying "Do not open front panels when debugging", which would only open the block diagram. Instead of the front panel you could only offer a list of all input/output controls (and maybe their values), and you could put this list in the same window for all open VIs (in some organized way - maybe similar to probe window). That way all front panels would only take up one window instead of many.
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