[Wintermute]

[ QUOTE ]
Why is it wrong to play a flopped straight with one weak re-draw (although it is a blocker)out of position very cautiously?

[/ QUOTE ]

Omaha Hi/Low 8-or-better: 820 enumerated boards containing Qc Tc Jd
cards scoop HIwin HIlos HItie LOwin LOlos LOtie EV
Kc 3c Ad Qd 550 550 270 0 0 0 0 0.671
Ac 9c Ah 5h 270 270 550 0 0 0 0 0.329

and

Omaha Hi/Low 8-or-better: 820 enumerated boards containing Qc Tc Jd
cards scoop HIwin HIlos HItie LOwin LOlos LOtie EV
Kc 3c Ad Qd 504 504 249 67 0 0 0 0.655
As Ts 7c Th 249 249 504 67 0 0 0 0.345

If you happen to get both to come along, as happened here:

Omaha Hi/Low 8-or-better: 666 enumerated boards containing Qc Tc Jd
cards scoop HIwin HIlos HItie LOwin LOlos LOtie EV
Kc 3c Ad Qd 256 256 349 61 0 0 0 0.430
As Ts 7c Th 220 220 385 61 0 0 0 0.376
Ac 9c Ah 5h 129 129 537 0 0 0 0 0.194

Why would you want to let them draw cheaply when you have a massive advantage is you can get all-in here? They are much less likely to commit chips on the turn unless they make their hand. Also, the fact that you're OOP is a reason FOR jamming on the flop--this is the best opportunity to get chips into the pot in the times they don't catch you. Finally, more often, you'll find yourself all in on a flop like this against a str with no redraw:

Omaha Hi/Low 8-or-better: 820 enumerated boards containing Qc Tc Jd
cards scoop HIwin HIlos HItie LOwin LOlos LOtie EV
Kc 3c Ad Qd 346 346 18 456 0 0 0 0.700
2s Ac Kh Jh 18 18 346 456 0 0 0 0.300

Now, there is a chance you're going to find yourself up against a hand that dominates yours:

Omaha Hi/Low 8-or-better: 820 enumerated boards containing Qc Tc Jd
cards scoop HIwin HIlos HItie LOwin LOlos LOtie EV
Kc 3c Ad Qd 65 65 225 530 0 0 0 0.402
Ac 9c 5c Kh 225 225 65 530 0 0 0 0.598

Omaha Hi/Low 8-or-better: 820 enumerated boards containing Qc Tc Jd
cards scoop HIwin HIlos HItie LOwin LOlos LOtie EV
Kc 3c Ad Qd 54 54 450 316 0 0 0 0.259
Ac Jc Kh Jh 450 450 54 316 0 0 0 0.741

But you have to put the opponent on a range of hands, and it's most likely you have his ass halfway into the frying pan, about to be severly blackened. In this case, OP got the worst possible situation--both players came along instead of just one, and the draws hit. But in the long run, shoving on the flop in this situation will definitely prove to be the best play.