Personally, I was disappointed in the Refurbished H.E.A.R.T. Rank VI when I earned it last month. The lack of initial heal boost makes it a non-starter for me. This is just one more reason to leave it one the counter in my house as a relic for others to view.
Good to know but the fact that you used your Resto chip in between makes the results inconclusive. The system keeps track of that stuff and 'reimburses' you at the next opportunity, so the 0.01 you got after using the tt fap could have been a 'reimbursement' for the decay on the resto chip which you incurred about 15-20 seconds earlier.
But it's clear the Refurb Heart decay was not compensated.