Apropos of fūdī, Alan Nussbaum reminds me that the root is *gh'ew- and that the -do/e- (an extension also seen in Goth. giutan 'to pour') of the Latin verb is in origin a present-forming suffix ( cf. pellō < *pel-dō vs. perf. pepulī < *pe-pol-). But if *-do/e- was a present formant, then the perf. fūd- has its -d- analogically from the present, and this favors an analogical explanation for fūdī, e.g. winko/e- : wi:k- = fundo/e- : X.