Well I dunno if there is a right or wrong answer to this debate.
I do know that I have been performing preflight inspections for years with and without engineering support.
I believe that where such support is available it should be used.
But if that support is not available, should the aircraft be grounded? I don't think so.
It does seem to me that the whole issue is a bit of a beat up for an industrial agenda.
While that may be appropriate I just can't but help remember all the times I have been told "don't write it up, we don't have licence coverage" or "if you write it up it will cause a delay".
I guess at the end of it I don't particularly like all the accusations and counter accusations between two professional outfits that depend on each other for support in order to keep flying safe and to keep us all gainfully employed. For evey pilot who misses a particular thing on a walkaround I would imagine someone can quote an engineer missing something.
It is not the pilots that have gone public here. But we can support the use of engineer inspections at bases where engineers are available. Would that help?