Raising 10's - people seem nervous about it

i've noticed that alot of people don't raise 10's pre-flop or feel comfortable about it and frankly i'm the same, although i realize that every major book says to do it (and we could argue J's or 9's, nothing too special about 10's. i think though that QQ, KK, AA are "no-brainer" raises for most)

so if you have a pair of 10's, there are 4 cards that can beat you (A, K, Q, J). but here's what i don't understand.. for each card on flop, do my opponents have 12 outs or 16 outs? i mean, i assume that my opponent has to have the card but then i don't know which one.

so assuming, they have 12 outs and 3 cards, that's 36 outs by simple method. although i did the math properly and there's 56.5% chance that a danger card hits and could be paired. but with 3 callers (hypothetically), i wouldn't give full weight to the Queen or Jack, cause less likely to play Q high or J high and if it was Q low or J low then they might have raised.

so changing the opponent outs to 9 (3 for ace, king, 1.5 for Q, J) means it's 45% that opponents hit pair a higher card. although 12.5% chance that you hit a 3rd 10 (but i don't think you can subtract 12.5% from 45%)... if i subtract the two odds per card, then it's 37% chance they hit.

once the flop comes with little danger you're in fantastic shape. A or K on flop (without 10) and you're dead. JQ i guess takes call, but decent chance you're ok.

ok, the odds make me feel much better about raising 10's. with 2 other callers, it's 2 to 1 (33%), with three other callers, it's 3 to 1 (25%). and it looks like 50% to 65% chance that i'm leading after flop. those are good odds.

one of the real keys is discounting the chance that Q or J have you beaten when they fall.

is my math analysis anywhere close? and am i right to use 3 outs for the Aces as the opponent has to have an ace in his pocket before the flop.

obviously i disregarded very complex flops i.e. 2 pairs etc.