Ask any NFL agent or salary cap guru and he’ll tell you that picking up the fifth-year option on Aldon Smith’s contract is the prudent, no-brainer move for the 49ers.

The Rams are doing that with their pass-rush specialist, Robert Quinn, and the Texans exercised the option with defensive lineman J.J. Watt. In fact, just about every team with a high pick in the talent-laden 2011 draft is expected to use the fifth-year option on its young, star player.

Doing so in San Francisco would allow the 49ers to lock in Smith, perhaps the most talented pass rusher in franchise history, through the 2015 season at a below-market cost and with minimal risk. Triggering the option would pay Smith $9.75 million next year, but it would not be guaranteed, except for major injury, until the start of the new league year March 15.

That is, it would allow the 49ers to cut ties with Smith if, 11 months from now, they still felt uneasy about the troubled outside linebacker.

The 49ers, however, are leaning against picking up that option. Why? Because they don’t think it’s the best thing for Smith. Doing so would send an odd message: We’re extremely unhappy about your recent behavior, but here’s a nearly $10 million reward.

What Smith needs are consequences, which to this point have been minimal for someone with so many serious issues in the past two years.

His 2012 DUI charge in Miami Beach – his blood-alcohol level registered .194 and .176, according to two breathalyzer tests given at the time, police said, far above the legal limit of .08 – was reduced to reckless driving. Later that year, he was stabbed at an out-of-control house party. Later still, he was involved in a rollover accident near his home. The 49ers arrived on the scene and took him to the hospital with which they are affiliated, Stanford Hospital, even though it is 30 miles from where the crash occurred.