(Think) Timers for Whole Transaction

Question

In OFT you used to be able to manually set timers across multiple steps e.g. if you were only really interested in 3 out of 7 steps you could just get that time as a seperate value. How can you do similar in OpenScript? I've tried putting a dummy step group around the actual steps but that doesn't appear to give me the total time I thought it might.
To be precise, what I'm trying to demonstrate is an artifically REDUCED Think Time script which is being tweaked so that it takes 60s to complete. The idea is that running 60VUs taking 60s each should give a throughput of around 1 transaction per second. The point being to show that "real-world" Think Times (which I suspect should be more like 2-3 minutes for this scenario) are important.
There are 7 steps in the scenario, only 3 of which actually have considerable Think Times, but what I really want to check is that the whole script takes an average of 60s to complete. What appears to be happening is that although OpenScript reports it as taking about 60s (59?) when the script is run in OLT with 60 users I'm actually seeing more like 1.2-1.5tps! I could understand it being LESS than 1tps but not more? I think I'm missing something obvious somehwere? I did spot that you can set a maximum think time in OpenScript but is there something similar in OLT? Is this purely because OLT is far more efficient than OpenScript because it's doing less?
Think Times are as follows (simplified figures)
1) 0ms
2) 25,000ms
3) 10,000ms
4) 2,000ms
5) 10,000ms
6) 2,000ms
7) 4,000ms
Total 53s Think Time (but the script runs in 59-60s).

Answer 1

Basically I'm trying to get a script to run for exactly 60s (I know it's not realistic but that's the point of the demonstration). In order to verify this I wanted to have a timer that would show on the OLT graphs for the WHOLE time each transaction takes end-to-end. There used to be an option in OFT to set a start and end timer so you could do this sort of thing, but I can't find similar in OpenScript.
What I found confusing was that when I added a dummy step group (surrounding my 7 'real' steps) to try and make the end-to-end time 'visible' it appears to be producing a value less than I expected. i.e. A script that takes 60s to run in OpenScript looks like it's only taking around 45-50s in OLT. Why does OLT appear to be completing the script in 50s as opposed to 60s in OpenScript?
i.e.
WholeTran (reports in OLT as around 50s but took 60s in OpenScript)
WholeTran.Step1
WholeTran.Step2
WholeTran.Step3
WholeTran.Step4
WholeTran.Step5
WholeTran.Step6
WholeTran.Step7