wheel sizes on trailers

I have four bicycle trailers. But I have
modified them so it is not possible to connect
them to bikes anymore, at least not the way it
was intended, as I have cut that part of the
front tube. This makes it easier to pull and
also when you have them all around moving
around and between them is easier without this
protruding/annoying part.

The trailers are very good for pulling.
For example, in one trailer one can pack 40-50
pieces of firewood!

Here [1] is what they look like.

Anyway, today I examined the tire sizes.
They are

2* 47-305 (16x1.75x2)
44-305 (16x1.75)
2 - 19 3/4 (24x2) (50-507?)

Here, we remember the interesting formula

roll-out = chainring/sprocket * wheel

However having neither chainring or sprocket,
what impact does the bicycle trailer wheel size
has, and how does that work? Impact not on the
bike but in general, I mean?

[1] http://user.it.uu.se/~embe8573/work-...pertramp-1.jpg
http://user.it.uu.se/~embe8573/work-...oasen-wood.jpg

--
underground experts united
http://user.it.uu.se/~embe8573