That's my biggest pet peeve, by far. Tanking doesn't mean you're not managing your team, it means you're not even attempting to field a competitive team. At the risk of turning this into a "look at me" post:
When I took back my Buffalo team in CAPB, the previous owners had all but destroyed the minors and a middling BL team. I traded away every one of my marketable BLers, but signed Type B or lesser FAs after the Rule 5 draft, just to stay competitive. I still have an uber-small payroll, but you can't sleep on my BL team, either. I'm in year two of the rebuild, have the lowest player payroll in the league, and currently sit at 74-84 at the big league level (73-89 last season). And I haven't had any of the prospects I've acquired at the big league level yet. The rebuild is still intact, I'm signing good draft picks and good IFAs, but I haven't lost 90 in a season (let alone 100, 110, 120, whatever). It's WAY too easy to build a cheap, fairly competitive team out of over free agents, and still have money to accumulate prospects, to excuse any "plan" that involves 100 loss seasons.