Our reason for embracing e-signatures in short: if you are going to have a single approach, you want that approach to serve all scenarios, including the most-complex.
In our validated LMS environment all training completions (classrooom, Virtual, eLearning, and Document) all require an e-signature (learner re-enters SSO credentials, ID and PSWD), whether the training items are or have an associated final test/quiz or not. One reason we don't rely on just a acknowledgment button is that while some training methods (especially DOCs) may use an AICC wrapper (with an "Agree" acknowledgment button to confirm the learner has read/understod the material), this is not a requirement for setup of all items and training methods. For example, while a DOC (read-and-acknowledge) does have an "Agree" button, typically the vast majority of elearnings do not because elearning courses impose their own completion criteria, whether requiring interaction, % test score, % media playback, and/or % slides viewed. Instead an elearning object sends a completion status to the LMS after the completion criteria has been met, and when the LMS tracks completion for all objects within the item the learner is then prompted to provide their SSO logon credentials to e-verify item completion.
I agree with an earlier post that an Agree button alone is too easy for a learner to click without doing anything more. And when the Agree button approach serves many training methods generically, it is a slippery slope to say that it proves much of anything in some scenarios. It is common today for training to contain multiple smaller content objects, not just a single content object or a single assessment object. Examples include an elearning presentation content object and assesment quiz object, or a DOC object with an assessment quiz object, or even more complex or hybrid approaches that require learners to complete 3-12+ content objects all within a single item. While some of these multi-object items may use the AICC wrapper (with simple Agree button to acknowledge completion of each object), other objects (like elearning) impose completion criteria that shouldn't be skipped with a simple Agree button, and still other objects may earn completion credit credit for simply launching the objects. A single e-signature for the entire item provides a single comprehensive/collective confirmation from the learner that they have successfully completed the entire training or activity.
