How useful are probability calculations from guesses?

[GlemZurg]

I have a question about how to estimate hand odds on the flop.

If I guess the number of outs for my hand (including partial outs),
If I guess the number of outs for my opponents (including partial outs),
If I guess the odds that I have the best hand at the moment,

Is the probability calculation meaningful for figuring pot odds or are the guesses to fuzzy to figure anything useful?

For example, on a flop, let say,
I *guess* I have 3 : 1 odds of best hand
I *guess* there are 8 cards that will make my hand the winner
I *guess* there are 4 cards that will make my opponents hand the winner

17.0% <-- 8/47 I win (my outs on 4th street)
08.5% <-- 4/47 they win (their outs on 4th street)
13.0% <-- 35/47 * 8/46 I win (my outs on 5th street)
06.5% <-- 35/47 * 4/46 they win (their outs on 5th street)
13.8% <-- 35/47 * 34/46 * 1/4 I win (unimproved best hand odds)
41.3% <-- 35/47 * 34/46 * 3/4 they win (unimproved best hand odds)

So they will win (8.5 + 6.5 + 41.3) = 56.3% of the time.
I will win the rest (100 - 56.3) = 43.7 of the time.

Which is odds of 1.3 : 1.

Are these final odds meaningful given the fuzzy inputs to the calculation?

Thanks,
Justin