Not sure what we can learn from this, apart from being reminded of the fickle nature of public and media opinion.
As for uniform, if MTP is working dress then I guess that is what is worn, remember LOCOG wanted the service personnel to wear the same gear as volunteers. The naval contingent (with exceptions) stayed clear of MTP, and were easily recognised in our no3s. If you were not deterred by the large numbers of armed police, then I think a few guys/girls on uniform would not put you off.