send proposal and contract vs proposal that is contract?

for example, I'm using Adobe sign. a client asked me to send a proposal and I didn't have time to prep up, so I sent adobe sign template PDF proposal with adobe sign included one same page for signature. Suprise he signed automatically. to me, it saved another step.

anyone else do this? cons and pros?

im only asking because I wonder how companies like infusionSOFT obtain clients with all their emails: training schedule setup, training appointments verifications, appointments, schedule calls, scheduled called verifications, proposals, proposal verification contract, etc... I counted 14 emails. It was a huge turn off. love to hear how fast you're able to close client with just a call and one email.