phaedrus wrote:
Just need to get these things clarified!

The velocity factor of a tx line is governed by its distributed
inductance and capacitance, is it not?

Yes.

I mean the more L and C you have per meter of line the lower the
signal velocity, right?

Right.

How much is the signal speed retarded by typically and are there any
circumstances where we need to be concerned about this phenomenon?

The velocity factor for air dielectric cables is essentially unity. The
slowest common velocity factor is about 0.66, which you'll find in coax
(where the field is entirely in the dielectric) having solid
polyethylene dielectric. Velocity factor is important in determining the
physical length of cable needed to effect a specific time or phase delay.

Roy Lewallen, W7EL