Becoming comfortable is different for each person. For example, veteran trainers may need more time to become familiar with equipment and may want more practice. I think distance learning is great, if it's appropriate for the subject matter and the training goes well. What worries me are the uncontrollable technical problems that can crop up. Also, trainers in the classroom don't have other trainers watching them.
Online support includes setting up the software, the servers, and the passwords.
In the classroom, if all else fails, you can rely on yourself and hard-copy materials. Having alternate plans for when technology goes haywire is also important. The objective of distance learning, in my case, is to connect remote learners who work from their homes, so no tech support is available. Remote home learners need a help line and a fax line, at a minimum. It sounds like trainers need a Dummies Guide to Tech Support because some don't have the two-trainer option.