Lukewarm Letter of Recommendation

[workwork]

Hi everyone! I'm applying to top programs (Harvard, MIT) for an MSRED degree. For those unfamiliar, you can think of this as a mini-MBA. I was wondering how critical it is to have strong letters of recommendation from work supervisors? I just got a copy from mine and while there were details about my contributions, the information about my skills or personality seemed brief. The entire letter only has 3 paragraphs! 

(1) Is this an application killer?

(2) Is there an understanding within adcomms that professional recommenders may not write in as much detail as academic?

(3) What are the elements of "strong" recommendation letters? 

I'm slightly freaking out!! Thank you!