The problem is that cranes are cyclical, relying on a strong economy, while food service is secular and remains pretty steady. That means if you're an analyst on Wall Street, Manitowoc is confusing. You're not going to recommend it as a pure construction play, nor as a restaurant play.

Cramer said valuing Manitowoc's crane business at nine times earnings gives it a value of $3.5 billion. The food service business fetches 12 times earnings and would fetch $4.25 billion.

That's a 42% premium over current valuations, Cramer concluded. With activist investors in the mix, management just might listen and unlock that value.

Credibility Scale

When a company misses earnings by a mile, how can you tell whether the CEO's excuse is legitimate or ridiculous? Cramer introduced his "Mad Money Credibility Scale" to analyze four recent retail implosions.

First up, The Container Store (TCS), which explained its poor results on a "retail funk" that's affecting all retailers. Cramer said on a scale of 1 to 10, he gives this excuse a 3 for believability.

Next up was Tractor Supply (TSCO), which once again blamed the weather for its second miss in a row. Cramer said this excuse gets an 8 on the scale because management confirmed that as the weather improved in the second half of the quarter so did sales.

Third was Lumber Liquidators (LL), whose drastic pre-announcement sent shares plunging 25%. The company blamed a weak macro economy and poor remodeling trends for its staggering losses. Cramer said this excuse receives a 2 on his scale.

Finally, there was Family Dollar (FDO), which reported its third miss in a row. The company said that its low-income shoppers were still getting squeezed by high unemployment and reduced government benefits. Cramer said this excuse scores a 1 on his scale as it's clear those shoppers are just spending elsewhere.

Following Nelson Peltz

Never, ever piggyback your investments off of what an activist or celebrity investor is doing, Cramer reminded viewers. Unless of course, that investor is Nelson Peltz.

Cramer said he never advocates trying to follow what big-time investors are doing because by the time their holdings are made public it's old news. Those same investors are under no obligation to update you on their intentions.

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