alanti:
The one thing I will add to what others have said is that the stats can be misleading. Take my stats, sand saves are at under 50% and scrambling is just over 50%. I used starters clubs till I made masters and at that stage these figure were at under 20%. They are slowly creeping up and I know the current stats would be closer to 60% and 75% minimum respectively. Putting stats too have been affected.
Having said that, for this reason it would be nice to have both career and current Tier stats showing to give a clearer indication of areas that you need to improve on. Yes current tier stats would be jumping like your average when hitting a new tier but they sone settle down.
If one thinks ahead it is very easy to create a spreadsheet into which you put all your stats at all the different milestones. Then it is easy to calculate anything at any time. I find it helpfull especially when changing clubs - to see exactly where I am sliping and where I am improving.