> The word /quadra:ginta:/ "forty" has voiced both former *t and
> *k to /d/ and /g/.
The voicing in quadra- quadru- forms is the only example of *tr > dr, and it
is not only unexplained, but also contradicts the usual development in the
opposite direction, dr > tr e.g. uter < utris ~ Greek hydr- or *taedros >
*taetros > taeter, cf taedet.
The voicing -g- is also unexplained (though various suggestions have been
made, involving clusters of voiced resonant + k')
Not very helpful, am I? But yoru idea can't really be sustained.
Peter