I went for H1B stamping at the end of January this year and I do had a long gap in my employment after OPT. This triggers the visa officer and gave me 221g. She told me to provide all the relevant documents from last 5 years to verify whether to approve the H1B or not. It was very stressful because it was hard to contact the employer and get all the relevant documents of backdated time. But I did not loose hope and slowly started gathering documents as much as I can and submit it after 2 weeks and waited for the response. After two and half weeks I was granted visa. I was lucky enough this time.

From my experience, If you have an long employment gap or you have join the college(non-credible) just for CPT purposes, then it would definitely haunt you back during the interview and it would be very difficult to get visa. Else if there is no employment gap, you have worked in OPT and then applied for H1B and working currently, then there will be no issues, you can go freely and get stamped easily. Above are the individual opinion based upon my experience.